CAIET DE LABORATOR
PENTRU CLASELE A IX-A ŞI A X-A
prof. ELL ELLEN PO POPOVI POVICI CI
1
ARGUMENT
Prin problematica problematica abordată abordată şi modul de structurare structurare a conţinutului, caietul de faţă este destinat deopotrivă elevilor şi profesorilor de fizică din licee. Scopul acestui caiet de laborator este acela de a prezenta una dintre nenumăratele variante în care se pot concepe fişele de lucru la orele de laborator pentru disciplina fizică. Lucrarea Lucrarea este un îndrumar care conţine atât materialul necesar desfăşurării lucrărilor de laborator, modul în care se utilizează acest material dar şi câteva idei de evaluare la activ activităţ ităţile ile practi practice ce.. Unele Unele lucrăr lucrării conţin conţin şi o parte parte teor teoretică etică neces necesară ară intr introduce oducerii rii în domeniul experimentat. Prin forma de prezentare, caietul poate substitui fişele de lucru ale elevilor, venind astfel în spriinul profesorilor de fizică şi al laboranţilor. Lucrările prezentate prezentate în cadrul acestui îndrumar constituie o bază pentru însuşirea însuşirea cunoştinţelor experimentale experimentale le!ate de disciplina fizică.
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CUPRINS Argument …… ………… ………… ………… ………… ………… ………… ………… ………… ………… ………… ………… ………… ………… ………… ……... .....
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CAPITOLUL I. Optic geometric ………......................................................................................... 5
I.1. I.1.
Obse Ob serv rvar area ea ref refle lexi xiei ei l! l!i" i"ii ii #i #i $e%e $e%er! r!i" i"ar area ea ex& ex&er eri! i!e" e"%a %al' l' a le( le(il il)r )r ei ei ………… …………....
5
I.2. I.2.
Obse Ob serv rvar area ea ref refra ra*+ *+ie ieii l!i" l!i"ii ii #i ver verif ifi* i*ar area ea ex& ex&er eri! i!e" e"%a %al' l' a le(i le(il) l)rr ei……… ei…………… ……....
,
I..
Observare Observareaa fe")!e" fe")!e"li li $e $e reflexie reflexie %)%al' %)%al' a l!i"ii l!i"ii #i $e%er!i"a $e%er!i"area rea "(i "(ili li li!i%' li!i%' /"
*a0l *a0l %re*erii %re*erii l!i"ii l!i"ii $i" $i" a&' a&' /" aer…… aer…………… ……………… ……………… ……………… ……………… ……………… …………. …. I.. I..
3e%e 3e %er! r!i" i"ar area ea i"$i i"$i*e *el lii $e refra refra*+ *+ie ie al "i "i !e$i !e$i %ra"s %ra"s&a &are re"% "%…… ………… ………… ………… …….. 11
I.5.
S%$il &r)&a('rii l!i"ii &ri" &ris!a )&%i*' #i $e%er!i"area i"$i*eli $e refra*+ie al
"ei &ris!e…… &ris!e…………… ……………… ……………… ……………… ……………… ……………… ……………… ……………… ……………… ………….. ….. 1 I.4. I.4.
3e%e 3e %er! r!i" i"ar area ea a&r) a&r)xi xi!a !a%iv %iv'' a $is%a $is%a"+ "+ei ei f)*a f)*ale le a "ei "ei le"% le"%il ilee sb+ sb+ir iri… i……… ………… ………. …... 15
I.,.
3e%er!i"a 3e%er!i"area rea $is%a" $is%a"+ei +ei f)*ale f)*ale a "ei "ei le"%ile le"%ile *)"v *)"ver( er(e"%e e"%e !e%)$ !e%)$aa 6essel 6essel7……… 7………........14
I.8. I.8.
S%$ S%$i ill " "ii i"s i"s%r %r! !e" e"%% )&% )&%i* i* l&a l&a77 ……… …………… ………… ………… ………… ………… ………… ………… ………. …. 18
CAPITOLUL II. Mec!nic ……………………………………………………………… 29
II.1. II.1. 3e%er! 3e%er!i"a i"area rea *)"s% *)"s%a"% a"%ei ei elas%i elas%i*e *e a "i res)r res)r%…… %………… ………… ………… ………… ………… ………… ……… … 29 II.2. 3e%er!i"area *)efi*ie"%li $e fre*are la al"e*are………………… al"e*are………………………………… ……………… 21 II.. II.. 3e%er! 3e%er!i"a i"area rea ra"$a! ra"$a!e"% e"%l lii "i sis%e! sis%e! !e*a" !e*a"i*… i*……… ………… ………… ………… ………… ………… …….... 22 II.. II.. Parale Paralel)( l)(ra! ra!l l f)r+ f)r+el) el)r…… r………… ………… ………… ………… ………… ………… ………… ………… ………… ………… ………… …… 2 II.5. II.5. E*il E*ilibr ibrl l "i "i *)r& sb sb a*+i a*+i"ea "ea "i "i sis% sis%e! e! $e f)r+e f)r+e…… ………… ………… ………… ………… ………… …… 25 II.4. Rela+ia Rela+ia $i"%re $i"%re (re%a%e (re%a%eaa "i *)r& #i !asa !asa sa............................................................................... 28 II.,. 3e%er!i"a 3e%er!i"area rea ex&eri!e" ex&eri!e"%al' %al' a val)rii a**ele a**elera+iei ra+iei (ravi%a+i) (ravi%a+i)"ale "ale.......................................... 2 ………… ………… ………… ………… ………… ………… ………… ………… ………… …….. 9 CAPITOLUL III. "enomene termice …… III.1. S%$il S%$il a!es%e a!es%e*li *li a $)' $)' li*i$e li*i$e * %e!&er %e!&era%ri a%ri $iferi%e…… $iferi%e…………… ……………… ……………. …….
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III.2. S%$il S%$il fierberi fierberiii a&ei a&ei la &resi &resi"ea "ea a%!)sferi* a%!)sferi*'' ")r!al' ")r!al'……. ……..……… .……………… ……………… ………
1 3
III.. S%$il fierberii a&ei sb sb "ivell &resi"ii a%!)sferi*e a%!)sferi*e ")r!ale.......................................... 2 III.. 3e%er! 3e%er!i"are i"areaa *a&a*i%'+ *a&a*i%'+ii ii *al)ri*e *al)ri*e a "i "i *al)ri!e%r *al)ri!e%r.…… .…………… ……….……… .……………… …………. …. III.5. 3e%er!i"area *'l$rii s&e*ifi*e a "i *)r&.................................................................................. CAPITOLUL IV. E#ectricit!te $i m!gneti%m ......................................................................................5
I:.1. I:.1. U%ili0area U%ili0area !l%i!e% !l%i!e%rli; rli;;;;;; ;;;;;;;;;; ;;;;;……… ……………… ……………… ……………… ……………… ……………… ……………… ……… 5 I:.2. I:.2. U%ili0are U%ili0areaa srsei srsei $e %e"si"e %e"si"e……… ……………… ……………… ……………… ……………… ……………… ……………… ………… … 4 I:.. I:.. 3e%er!i"area re0is%e"+ei ele*%ri*e a "ei &)r+i"i $e *ir*i% ................................................... , I:.. I:.. S%$il $e&e"$e"+ei re0is%e"+ei ele*%ri*e $e l; S #i <................................................................... 8 ............................................................................................................................ I:.5. =r&area re0is%)ril)r .............................................................................................................................. ..................................................................................................... 9 I:.4. :erifi*area le(ii I a li >ir*)ff .....................................................................................................
I:.,. 3e%er!i"area &%erii "i be*.......................................................................................................... 1 I:.8. S%$il %ra"sf)r!a%)rli.................................................................................................................... 2 I:.. Efe*%ele *re"%li ele*%ri*................................................................................................................. I:.19. I"%era*+i"ea *re"+il)r ele*%ri*i..................................................................................................... 4 Bi&#iogr!fie ...................................................................................................................................................... ,
4
CAPITOLUL I. Optic! geometric I.'. O&%er(!re! ref#e)iei #uminii $i *etermin!re! e)periment!# ! #egi#or ref#e)iei
Scopul experimentului" )bservarea fe")!e"li fe")!e"li $e reflexie r eflexie a l!i"ii #i $e%er!i"area &e *ale ex&eri!e"%al' a le(il)r reflexiei l!i"ii? #eoria lucrării" Reflexia l!i"ii es%e fe")!e"l $e s*i!bare a $ire*+iei $e &r)&a(are a l!i"ii; a%"*i *@"$ ea /"%@l"e#%e s&rafa+a $e se&arare $i"%re $)' !e$ii )&%i*e $iferi%e; l!i"a /"%)r*@"$-se /" !e$il $i" *are a ve"i%. S
O
i "(i $e i"*i$e"+'
R
r "(i $e reflexie i
r
I &"*% $e i"*i$e"+' n'
me*iu# '
OOB $rea&%a $rea&%a &er&e"$i* &er&e"$i*lar' lar' &e &la"l $e se&arare $i"%re
me*iu# +
n+
I
+
i
O′
*ele $) $)' ' !e$ !e$ii )& )&%i %i*e *e ; /" &"*%l $e i"*i$e"+' ")r!ala la &la"l $e se&arare7
$ateriale necesare" necesare"$is* (ra$a% ar%l7;)(li"$' &la"';ba"* )&%i* * srs' $e l!i"'la!&'7?
$od de lucru" Se !)"%ea0' ba"*l )&%i* #i se a#a0' )(li"$a &la"' &e $is*; as%fel /"*@% ")r!ala la &la"l )(li"0ii s' fie *iar axa $ia!e%ral' OOB a $is*li.
C aD%)rl l'!ⅈ %ri!i%e+i ) ra0' $e l!i"' s&re )(li"$'. Observa+i *e se /"%@!&l' * ra0a $e l!i"' la s&rafa+a $e se&arare $i"%re *ele $)' !e$ii aer #i !a%eriall )(li"0ii7 I$e"%ifi*a+i ra0a i"*i$e"%' #i ra0a refle*%a%' $e )(li"$'; a&)i "(irile $e i"*i$e"+' #i $e reflexie. R)%i+i 5
$is*l as%fel /"*@% s' se !)$ifi*e "(il $e i"*i$e"+' al ra0ei &e )(li"$a &la"'. Ci%i+i &e $is* val)rile "(iril)r $e i"*i$e"+' #i a "(iril)r $e reflexie *)res&"0'%)are . N)%a+i val)rile *i%i%e; /" %abell $e !ai D)s. C)!&ara+i val)rile "(iril)r $e i"*i$e"+' * val)rile "(iril)r $e reflexie *)res&"0'%)are. Ung,i *e inci*en- i gr!*e/ ung,i *e ref#e)ie r gr!*e/
%erinţă & R's&"$e+i; /" s*ris; la /"%reb'rile $e !ai D)s "
a7. C! s"% val)rile "(iril)r $e reflexie; fa+' $e val)rile "(iril)r $e i"*i$e"+' *)res&"0'%)areF Ce rela+ie !a%e!a%i*' a! &%ea s*rie /"%re "(il $e i"*i$e"+' #i "(il $e reflexieF ................................................................................................................................... b7. Observa+i $is&"erea ra0el)r i"*i$e"%' SI7; refle*%a%' IR7 #i a ")r!alei la &la"l )(li"0ii OOB7; a&)i s*rie+i *! s"% ele $is&se ...................................................................................................................................................... *7. 3a*' " a+i fi av% la /"$e!@"' ) %rs' $e )&%i*'; a+i fi &%% $e%er!i"a ex&eri!e"%al le(ile reflexiei l!i"iiF 3es*rie+i; &e s*r%; *e !a%eriale a+i f)l)si #i *! a+i &r)*e$a ....................................................................................................................................................... ....................................................................................................................................................... .......... ............................................................................................................................................ ....................................................................................................................................................... ...................................................................................................................................................... 'valuarea activităţii elevilor
N!ele elevliG (r&ei
Ci%irea Reali0area !)"%aDli $a%el)r #i 2 &"*%e7 *)!&le%area %abelli 2 &"*%e7
R's&"s *)re*% la *eri"+a a7. 2 &"*%e7
R's&"s *)re*% la *eri"+a b7. 2 &"*%7
R's&"s *)re*% la *eri"+a *7. 1 &"*%7
N)%a fi"al'
6
I.+. O&%er(!re! refr!c-ei #uminii $i (erific!re! e)periment!# ! #egi#or refr!c-iei
Scopul experimentului" )bservarea fe")!e"li $e refra*+ie a l!i"ii #i $e%er!i"area; &e *ale ex&eri!e"%al'; a le(il)r refra*+iei l!i"ii? #eoria lucrării" Refra*+ia l!i"ii es%e fe")!e"l $e s*i!bare a $ire*+iei $e &r)&a(are a l!i"ii; a%"*i *@"$ ea /"%@l"e#%e s&rafa+a $e se&arare $i"%re $)' !e$ii )&%i*e $iferi%e; l!i"a %re*@"$ /" *el $e-al $)ilea !e$i. S
O
n'0 n+
i "(i $e i"*i$e"+' r "(i $e refra*+ie I &"*% $e i"*i$e"+'
i
Me*iu# '
n' I
OOB $rea&%a &er&e"$i*lar' &e &la"l $e se&arare $i"%re
Me*iu# +
n+
*ele $)' !e$ii )&%i*e ; /" &"*%l $e i"*i$e"+' ")r!ala
O1
r
la &la"l $e se&arare7 R
$ateriale necesare" $is* (ra$a% ar%l7; *ase%' $e refra*+ie; ba"* )&%i* * srs' $e l!i"' la!&'7; %abele !a%e!a%i*e? $od de lucru" Se !)"%ea0' ba"*l )&%i* #i se a#a0' *ase%a $e refra*+ie &e $is*; as%fel /"*@%
")r!ala la &la"l $e se&arare $i"%re *ele $)' *)!&ar%i!e"%e ale *ase%ei s' fie *iar axa $ia!e%ral' OOB a $is*li. L'sa+i ()l *)!&ar%i!e"%l )rie"%a% s&re la!&' aerl $i" *)!&ar%i!e"% va *)"s%i%i !e$il 17 #i !&le+i *)!&ar%i!e"%l al $)ilea * a&' a&a va *)"s%i%i !e$il 2 7.
. C aD%)rl l'!ⅈ %ri!i%e+i ) ra0' $e l!i"' s&re *ase%a $e refra*+ie. Observa+i *e se /"%@!&l' * ra0a $e l!i"' la s&rafa+a $e se&arare $i"%re *ele $)' !e$ii I$e"%ifi*a+i ra0a i"*i$e"%' #i 7
ra0a refra*%a%' la s&rafa+a $e se&arare $i"%re *ele $)' *)!&ar%i!e"%e; a&)i "(irile $e i"*i$e"+' #i $e refra*+ie. R)%i+i $is*l as%fel /"*@% s' se !)$ifi*e "(il $e i"*i$e"+' al ra0ei &e s&rafa+a $e se&arare. Ci%i+i &e $is* val)rile "(iril)r $e i"*i$e"+' #i a "(iril)r $e refra*+ie *)res&"0'%)are.. Ha*e+i !ai !l%e !'sr'%)ri; &e"%r "(iri $e i"*i$e"+' $iferi%e #i ")%a+i val)rile *i%i%e; /" %abell $e !ai D)s. C)!&le%a+i *)l)a"ele ; ; 5 #i 4 ale %abelli; #%ii"$ *' i"$i*ii $e refra*+ie ai *el)r $)' !e$ii s"% " aer 1 iar " a&' 1;7 ; f)l)si"$ %abelele !a%e!a%i*e &e"%r a ('si si"sl fie*'ri "(i /" &ar%e. Ung,i *e inci*en- ung,i *e refr!c-ie r gr!*e/ Sin i Sin r n!er 2%in i i gr!*e/
n!p 2%in r
%erinţe"
a7. C)!&ara+i *)l)a"a a :-a a %abelli * *)l)a"a a :I-a #i s*rie+i *e )bserva+i Ce rela+ie !a%e!a%i*'; *are s' le(e si"srile "(iril)r $e i"*i$e"+' #i $e refra*+ie; $e i"$i*ii $e refra*+ie ai *el)r $)' !e$ii; a! &%ea s*rieF ...................................................................................................................................................... b7. Observa+i $is&"erea ra0el)r i"*i$e"%' SI7; refra*%a%' IR7 #i a ")r!alei la &la"l $e se&arare OOB7; a&)i s*rie+i *! s"% ele $is&se ....................................................................................................................................................... ...................................................................................................................................................... 'valuarea activităţii elevilor
N!ele elevliG (r&ei
Reali0area Ci%irea $a%el)r !)"%aDli #i *)!&le%area 2 &"*%e7 *)l)a"el)r 1;2 $i"%abel 2 &"*%e7
C)!&le%area *)re*%' a *)l)a"el)r ;;5;4 $i" %abel 2 &"*%e7
R's&"s *)re*% la *eri"+a a7. 2 &"*%7
R's&"s *)re*% la *eri"+a b7. 1 &"*%7
N)%a fi"al'
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I.3. O&%er(!re! fenomenu#ui *e ref#e)ie tot!# ! #uminii $i *etermin!re! ung,iu#ui #imit
Scopul experimentului" )bservarea fe")!e"li $e reflexie %)%al' a l!i"ii #i $e%er!i"area "(ili li!i%' /" *a0l %re*erii l!i"ii $i" a&' /" aer? #eoria lucrării" La %re*erea l!i"ii $i"%r-" !e$i * i"$i*e $e refra*+ie !ai !are /"%r-"
!e$i * i"$i*e $e refra*+ie !ai !i*; &e !'sr' *e "(il $e i"*i$e"+' *re#%e; se !'re#%e #i "(il $e refra*+ie; ra0a refra*%a%' a&r)&ii"$-seJ $e s&rafa+a $e se&arare $i"%re *ele $)' !e$ii. Pe"%r " a"!i% "(i $e i"*i$e"+' "!i% "(i li!i%' i(l 7; ra0a es%e refra*%a%' /" l"(l s&rafe+ei $e se&arare; "(il $e refra*+ie fii"$; /" a*es% *a0 $e 9K. S
n'4n+
O
3a*' "(il $e i"*i$e"+' *re#%e &es%e "(il li!i%' i)l 7; " !ai
i 5 l
exis%'
l!i"a I
n'
me*iu# ' me*iu# +
r 5 678
n+
ra0'
se
refra*%a%';
refle*%'
%)%al;
/"%)r*@"$-se /" !e$il $i" *are a
ve"i%.
He")!e"l
&)ar%'
"!ele $e reflexie totală. n1 sin l = n2 sin r $i r = 90°
O1
sin 90° = 1/
:al)area
sin l = n2 / n1
"(ili
li!i%'
$e&i"$e $)ar $e i"$i*ii $e refra*+ie ai *el)r $)' !e$ii. $ateriale necesare" $is* (ra$a% ar%l7; *ase%' $e refra*+ie; ba"* )&%i* * srs' $e l!i"' la!&'7; %abele !a%e!a%i*e?
$od de lucru" Se !)"%ea0' ba"*l )&%i* #i se a#a0' *ase%a $e refra*+ie &e $is*; as%fel /"*@%
")r!ala la &la"l $e se&arare $i"%re *ele $)' *)!&ar%i!e"%e ale *ase%ei s' fie *iar axa 9
$ia!e%ral' OOB a $is*li. U!&le+i * a&' *)!&ar%i!e"%l )rie"%a% s&re la!&' a&a $i" *)!&ar%i!e"% va *)"s%i%i !e$il 17 #i lasa+i-l ()l &e *el'la% aerl va *)"s%i%i !e$il 2 7. C aD%)rl l'!ⅈ %ri!i%e+i ) ra0' $e l!i"' s&re *ase%a $e refra*+ie. I$e"%ifi*a+i ra0a i"*i$e"%' #i ra0a refra*%a%'; a&)i "(irile $e i"*i$e"+' #i $e refra*+ie. Observa+i *e se /"%@!&l' * ra0a $e l!i"' refra*%a%' ; a%"*i *@"$ !'ri+i "(il $e i"*i$e"+' R)%i+i $is*l &@"' *@"$ ra0a se refra*%' $e-a l"(l s&rafe+ei $e se&arare. Ci%i+i #i ")%a+i /" %abel; val)area "(ili $e i"*i$e"+' &e"%r *are se /"%@!&l' a*es% l*r; a$i*' val)area "(ili li!i%'; l. Ung,iu# #imit m%ur!t *irect9 pe *i%cu# gr!*!t
In*ice#e *e refr!c-ie !&%o#ut !# !pei
In*ice#e *e refr!c-ie !# !eru#ui
Sinu%u# ung,iu# #imit *e*u% *in c!#cu#
l gr!*e/
n1
n2
sin l' = n 2 / n1
l ′ = arcsin n2/ n1
Diferen-! *intre ung,iu# #imit m%ur!t $i ung,iu# #imit c!#cu#!t
gr!*e/ '933
%erinţe"
Ung,iu# #imit *e*u% *in c!#cu#
Δl = | l – l ′|
'
a7. Cal*la+i val)area "(il li!i%' l ′ , /" *a0l reflexiei %)%ale a l!i"ii; la
%re*erea $i" a&' /" aer #i *)!&le%a+i %abell $e !ai ss f)l)si+i Tabelele !a%e!a%i*e7. ........................................................................................................................................................ b7. C)!&ara+i val)rile "(iril)r l * l ′#i s&"e+i *are ar fi &)sibilele srse $e er)ri.
...................................................................................................................................................... ..................................................................................................................................................... *7. Cal*la+i "(il li!i%' /" *a0l reflexiei %)%ale a l!i"ii; la %re*erea $i" s%i*l' /" aer; $a*' i"$i*ele $e refra*+ie al s%i*lei es%e " s%i*l' 1;5. ...................................................................................................................................................... ...................................................................................................................................................... 'valuarea activităţii elevilor
N!ele elevliG (r&ei
Reali0area Ci%irea C)!&le%area R's&"s !)"%aDli $a%el)r #i *)re*%' a *)re*% la 2 &"*%e7 *)!&le%area *)l)a"el)r *eri"+a b7. *)l)a"ei 1 ; 5; 4 $i" 2 &"*%7 $i" %abel %abel 2 &"*%e7 2 &"*%e7
R's&"s *)re*% la *eri"+a *7. 1 &"*%7
N)%a fi"al'
10
I.:. Determin!re! in*ice#ui *e refr!c-ie !# unui m!teri!# tr!n%p!rent
Scopul experimentului $e%er!i"area i"$i*eli $e refra*+ie al "i !a%erial %ra"s&are"%? #eoria lucrării I"$i*ele $e refra*+ie are ) val)are *ara*%eris%i*' &e"%r fie*are sbs%a"+'
)!)(e"'; *)res&"0'%)r fie*'rei l"(i!i $e "$' . Ur!'%)area !e%)$' es%e "a f)ar%e si!&l' &e"%r $e%er!i"area val)rii a&r)xi!a%ive a i"$i*eli $e refra*+ie al "ei sbs%a"+e;
*are &)a%e fi %ili0a%' $ire*% $)ar a%"*i *@"$ ave! la $is&)0i+ie " bl)* $i" sbs%a"+a res&e*%iv'; sb f)r!a "i &araleli&i&e$ $re&%.
R!;! inci*ent P' P+
A
C
i
B
r
O
D
O1 i'
P3
n+
P:
R!;! emerge nt
6l)*l %ra"s&are"% f)r!ea0' ) la!' * fe+e &la" &aralele. O ra0' $e l!i"' e!er(e"%' iese $i" la!a * fe+e &la" &aralele; $&' *e a s%r'b'%%-); &aralel* ra0a i"*i$e"%' . i = i ' /; /" r!a a $)' refra*+ii sferi%e &e fe+ele la!ei; &ri!a /" &"*%l O #i a $)a /" &"*%l O B. 3i" le(ea refra*+iei; /" &"*%l O; &%e! s*rie n1 sin i = n2 sin r ? C! bl)*l se afl' /" aer; n1 = 1 =
; 3i" %ri"(ilAO6;
=
#i $i" %ri"(il OC3;
=
. 3ar
AO O3 ra0a *er*li * *e"%rl /" O n2 = $ateriale necesare srs' $e l!i"' la!&'7; bl)* %ra"s&are"% * $)' fe+e &la" &aralele; $iafra(!' * ) si"(r' fa"%'; 'r%ie alb'; &i)"e0e; *)!&as? 11
$od de lucru U%ili0@"$ &i)"e0e; fixa+i ) f)aie $e @r%ie &e &la"l $e l*r #i &"e+i
bl)*l $e s%i*l'; &e fa+a !ai !are; /" *e"%r. C " *rei)" %rasa+i *)"%rl bl)*li $e s%i*l' &e @r%ie. Tri!i%e+i ) ra0' $e l!i"' *'%re bl)* #i &"e+i $)' a*e; P 1 #i P2 ; &e $ire*+ia ra0ei i"*i$e"%e. Cele $)' a*e s"% fixa%e &e &la"l $e l*r; as%fel /"*@%; li"ia $rea&%' *are %re*e &ri"%re ele s' f)r!e0e * !ar(i"ea bl)*li " "(i $e%er!i"a% "(il $e i"*i$e"+'7. Privi"$ $i"*)l) $e bl)*l $e s%i*l'; i$e"%ifi*a+i ra0a e!er(e"%' #i &"e+i $e-a l"(l ei al%e $)' a*e. S*)a%e+i s%i*la #i a*ele; a&)i $ese"a+i $ire*%ia re0el)r i"*i$e"%'; e!er(e"%'; $&' r!ele a*el)r #i $ire*+ia ra0ei &ri" bl)*. Trasa+i * *)!&asl " *er* * *e"%rl /" &"*%l $e i"*i$e"+' O. 3&' *e a+i $ese"a% se(!e"%ele *a /" fi(ra $e !ai ss; !'sra+i se(!e"%ele A6 #i C3; a&)i *al*la+i n . Re&e%a+i &r)*e$ra $e !ai !l%e )ri #i *)!&le%a+i %abell.
Nr. *et.
AB cm/
CD cm/
+ + + +
n5
=
1. 2. . . 5.
'valuarea activităţii elevilor
N!ele elevliG elevil)r (r&ei
Reali0area !)"%aDli
Reali0area $ese"li
1 &"*%7
&"*%e7
M'srarea se(!e"%el)r A6 #i C3 2 &"*%e7
Cal*ll i"$i*eli $e refra*+ie 2 &"*%7
N)%a fi"al'
12
I.<. Stu*iu# prop!grii #uminii prin pri%m! optic
Scopul experimentului s%$il &r)&a('rii l!i"ii &ri"%r-) &ris!' )&%i*' #i $e%er!i"area i"$i*eli $e refra*+ie al a*es%eia? #eoria lucrării Pris!a )&%i*' es%e " !e$i %ra"s&are"% li!i%a% $e $)' fe+e &la"e "e&aralele. Ea $evia0' ra0ele $e l!i"' i"*i$e"%e #i &)a%e se&ara l!i"a i"*i$e"%' /" *l)rile *)!&)"e"%e. L!i"a alb' es%e ) s&ra&"ere $e !ai !l%e *)!&)"e"%e *l)riG"$e7 * l"(i!i $e "$' $iferi%e. Se&ararea *l)ril)r se &r)$*e $e)are*e *l)rile $iferi%e se $e&lasea0' * vi%e0e $iferi%e &ri" &ris!' $e#i; &ri" vi$; ele se $e&lase0' * a*eea#i vi%e0'7. Ca r!are; fe")!e"l $e refra*+ie fa*e *a; la %re*erea &ri" &ris!'; *)!&)"e"%ele l!i"ii s' fie $evia%e sb "(iri $iferi%e. Me%)$a $e !'srare a i"$i*eli $e refra*+ie se ba0ea0' &e !'srarea "(ili $e $evia+ie !i"i!' δm . 3evia+ia es%e !i"i!' *@"$ "(il $e i"*i$e"+' i es%e e(al * "(il $e
e!er(e"+' i ' ; *eea *e &res&"e !ersl si!e%ri* al ra0ei $e l!i"'
&ri" &ris!'. i = i ' r = r ' şi A = r + r '
A
*eci r = A/2 δm = 2 i – A
i
r r1
−
δm
i
'
%!u
= +
B
n
=
C
$ateriale necesare" ba"* )&%i* * srs' $e l!i"'; $iafra(!' * ) fa"%'; s&)r% &ris!'; &ris!e * se*+i"i %ri"(i e*ila%eral #i %ri"(i is)s*el; e*ra"; %abele !a%e!a%i*e? $od de lucru Tri!i%e+i ) ra0' $e l!i"' s&re &ris!a * se*+i"e %ri"(i e*ila%eral #i r)%i+i #)r s&)r%l &ris!ei &@"' *@"$ )bserva+i i!a(i"ea *)l)ra%' a fa"%ei &e e*ra".
!
&
tg
5
5 !rc tg
13
A cm/
& cm/ 5 !rc tg
A ung,iu# pri%mei/
+
=
49K
%erinţe"
a7. Reali0a+i ex&eri!e"%l $e !ai ss #i *)!&le%a+i %abell; f)l)si"$ %abelele !a%e!a%i*e? b7. H)l)si"$ ba"*l )&%i*; la!&a; $is*l ar%l; ) &ris!' * se*+i"e %ri"(i is)s*el #i ) $iafra(!' * fa"%e; reali0a+i " !)"%aD * aD%)rl *'ria s' s%$ia+i !ersl ra0el)r $e l!i"' &ri" &ris!'. A#e0a+i &ris!a /" !)$rile ils%ra%e /" fi(rile $e !ai D)s.
*7. Ex&li*a+i *! !er( ra0ele $e l!i"'; /" fie*are $i"%re *ele *a0ri /" &ar%e. ....................................................................................................................................................... ....................................................................................................................................................... ....................................................................................................................................................... ........................................................................................................................................................ 'valuarea activităţii elevilor
N!ele elevliG elevil)r (r&ei
Reali0area *eri"+ei a7. &"*%e7
Reali0area *eri"+ei b7. &"*%e7
Reali0area *eri"+ei *7. 2 &"*%e7
N)%a fi"al'
14
I.=. Determin!re! *i%t!n-ei foc!#e ! unei #enti#e %u&-iri cu !pro)im!-ie/
Scopul experimentului $e%er!i"area * a&r)xi!a+ie a $is%a"+ei f)*ale a "ei le"%ile bi*)"vexe? #eoria lucrării" Le"%ila sb+ire es%e le"%ila *are are $is%a"+a $i"%re v@rfri !l% !ai !i*' $e*@% ra0a $e *rbr'. O1
B
>' "
O
"
!)! optic princip!#
I
A
? >+ f
?))''
I1
)+
3i" e*ivale"+a %ri"(iril)r OAO B #i AI
IB
%ri"(iri e*ivale"%e; A6H #i HI I B
5
−
? Mai exis%' ) &ere*e $e
5
−
5
−
@
5
−
H)*arl i!a(i"e H es%e &"*%l /" *are le"%ila s%r@"(e ra0ele &aralele * axa )&%i*' &ri"*i&al'; ra0e *e vi" $e la " )bie*% /"$e&'r%a% *a0 /" *are; se *)"si$er' x 1 7; iar f)*arl )bie*% H es%e &"*%l $e &e axa )&%i*' a *'rei i!a(i"e se f)r!ea0' la i"fi"i% se *)"si$er' x 1 7. " 8
" 8
$ateriale necesare le"%il' *)"ver(e"%'; )bie*% )are*are; s&)r% &e"%r le"%il'; ri(l'? $od de lucru" Pri" )bservarea "i )bie*% &ri"%r-) le"%il' *a /" i!a(i"e7 se &)a%e es%i!a
$is%a"+a f)*al' a "ei le"%ile. "$e&'r%@"$ le"%ila $e )bie*%; ")%a+i $is%a"+a la *are )bie*%l /"*e&e s' se va$' "e*lar. A*eas%a es%e $is%a"+a f)*al' a le"%ilei. U" al% !)$ es%e a*ela $e a )bserva *el !ai !i* &"*% l!i")s &r)$s $e ) le"%il' *)"ver(e"%';ex&s' la " fas*i*l &aralel $e l!i"' s&re exe!&l S)arele7; &e ) s&rafa+'. 3is%a"+a $i"%re le"%il' #i s&rafa+' es%e $is%a"+a f)*al'. %erinţe" 3e%er!i"a+i $is%a"+a f)*al' a "ei le"%ile *)"ver(e"%e;
&ri" *ele $)' !)$ri $e !ai ss; *'%@"$-v' &r)&riile &r)*e$ee $e a fa*e !'sr'%)rile; /" s*)&l ")r $e%er!i"'ri *@% !ai &re*ise &)sibil 15
I.. Determin!re! *i%t!n-ei foc!#e ! unei #enti#e %u&-iri meto*! Be%%e#/
Scopul experimentului $e%er!i"area $is%a"+ei f)*ale a "ei le"%ile bi*)"vexe? #eoria lucrării" O !e%)$' si!&l' &e"%r $e%er!i"area $is%a"+ei f)*ale f a "ei le"%ile
*)"s%' /" a!&lasarea le"%ilei /"%re )bie*%l l!i")s O #i " e*ra" fix; &e *are se )b+i"e i!a(i"ea I; si%a%e la $is%a"+a l "l $e al%l. " &)0i+ia A a le"%ilei; x*)x+ ; i!a(i"ea )b+i"%' fii"$ !ai !are $e*@% )bie*%l. Mi#*'! le"%ila * $is%a"+a d ; &@"' se )b+i"e ) al%' i!a(i"e *lar' &e e*ra"; i!a(i"ea )b+i"%' fii"$ !ai !i*' $e*@% )bie*%l; /"%r*@% x+ )x* . H)r!la le"%ilel)r; a&li*a%' /" *ele $)' A
*a0ri; se s*rieL
B
O
d
1
I
1
+
1
1
+
l
1
=
1
=
=e)!e%ri*; - / ( l d . Ca &"*%e *)"D(a%e fa+' $e le"%il'; (-/ şi - ( / deci
re0l%' *' - (
−
−
#i - + -(
+
+ = 2
2
( -/ . 3ar; OA x1 #i AI x2;
2
$e*i 1
+
1
= 1
1
=
4
f =
−
2 2 −
2
1
3is%a"+a f)*al' se &)a%e $e%er!i"a #i f'r' s' *")a#%e! re0ele $e *rbr' ale fe+el)r le"%ilei; $)ar &ri" !'srarea $is%a"+ei l $i"%re )bie*% #i e*ra" #i a $e&las'rii $ a le"%ilei. $ateriale necesare" ba"* )&%i* * la!&'; le"%il' *)"ver(e"%'; s&)r% &e"%r le"%il'; e*ra"; $iafra(!' * ) fa"%'? $od de lucru Reali0a+i !)"%aDl *a /" fi(ra $e !ai D)s.
16
Se ale(e ) $is%a"+' l /"%re srs' #i &arava" *are se !e"+i"e *)"s%a"%' /" *rsl "ei $e%er!i"'ri. Ea %rebie aleas' sfi*ie"% $e !are; l >4 f &e"%r a se )b+i"e $)' i!a(i"i $is%i"*%e #i *lare &e &arava"7. Se *a%' *ele $)' &)0i+ii ale le"%ilei &e"%r *are se )b+i" i!a(i"i *lare #i se !'s)ar' &e ba"*l )&%i* $is%a"+a d $i"%re a*es%e &)0i+ii. Ale(@"$ $iferi%e $is%a"+e l $ar sfi*ie"% $e !ari7; se v)r !'sra $iferi%e $is%a"+e d /"%re &)%i+iile le"%ilei *are $a $)' i!a(i"i *lare. :al)rile v)r fi /"l)*i%e /" rela+ia *are $' $is%a"+a f)*al'. Se va fa*e ) !e$ie a val)ril)r )b+i"%e &e"%r $is%a"+a f)*al' a le"%ilei. Re0l%a%ele se v)r %re*e /" %abell $e !ai D)s. Nr d!t
" #cm$
d #cm$
−
f =
=
++ +
#cm$
#cm$
1. 2. . .
Cal*le.......................................................................................................................................... ....................................................................................................................................................... ....................................................................................................................................................... ....................................................................................................................................................... ....................................................................................................................................................... ....................................................................................................................................................... 'valuarea activităţii elevilor
N!ele elevliG elevil)r (r&ei
Reali0area *eri"+ei a7. &"*%e7
Reali0area *eri"+ei b7. &"*%e7
Reali0area *eri"+ei *7. 2 &"*%e7
N)%a fi"al'
17
I.. Stu*iu# unui in%trument optic #up!/
Scopul experimentului s%$il &r)&a('rii l!i"ii &ri" l&' #i $e%er!i"area (r)sis!e"%li
=7; a &%erii )&%i*e P7; #i a $is%a"+ei f)*ale f7 a "ei l&e? #eoria lucrării L&a es%e
B
)
le"%il'
*)"ver(e"%'
*
$is%a"+' f)*al'; /" (e"eral; !i*'; /"%re 2 *! #i 19 *!.
L
>+
Obie*%l es%e a#e0a% /"%re l&' B
I
> '
A
A
#i &la"l f)*al; )b+i"@"$-se; "
+
O
as%fel; ) i!a(i"e vir%al'; $rea&%' #i !ai !are $e*@% )bie*%l. " &ra*%i*'; )bie*%l A6 es%e si%a% f)ar%e a&r)a&e $e
f)*ar; A% ≅ f . %aracteristicile lupei
Putere! optic P/ se $efi"e#%e *a ra&)r%l $i"%re %a"(e"%a "(ili sb *are se ve$e
i!a(i"ea )bie*%li 27 #i $i!e"si"ea li"iar' a )bie*%li Q 17. P ( t! * 0 1+ $ar t! * ( 1+ 0f P5'f . 3e*i; &%erea )&%i*' a "ei l&ei es%e e(al' * *)"ver(e"+a ei.
Gro%i%mentu# G/ es%e ra&)r%l $i"%re %a"(e"%a "(ili sb *are se ve$e i!a(i"ea
)bie*%li 27 #i %a"(e"%a "(ili sb *are se ve$e )bie*%l * )*il liber 17 . C@"$ se &rive#%e " )bie*% * )*il liber; el se a#a0' la $is%a"+a !i"i!' a ve$erii *lare &e *are ) ")%'! * 2. Pe"%r )*il ")r!al; f'r' ef)r% $e a*)!)$are; 2 25*!. C *@% "(il 1 ; sb *are se &rive#%e )bie*%l; es%e !ai !are; i!a(i"ea f)r!a%' &e re%i"' es%e !ai !are. B
oc,i
>'
3 ( t! * 0 t! + #i t! + ( 1+ 02 & = δ/f
sa & = δ
'
=r)sis!e"%l es%e " "!'r .
A
3a*' l&a are " (r)sis!e"% e(al *
5; /"sea!"' *' l&a !'re#%e $e 5 )ri.
$ateriale necesare le"%il' *)"ver(e"%' f 5 *!; @r%ie !ili!e%ri*' sa * &'%r'+ele; ri(l'? $od de lucru U%ili0a+i ) le"%il' $i" lab)ra%)r *a &e ) l&'. Obie*%ele *are s"% !ai a&r)a&e $e*@% &"*%l f)*al v)r a&'rea !'ri%e $e le"%il'. "*er*a+i a*es% l*r +i"@"$ le"%ila
a&r)a&e $e b*a%a $e @r%ie. Privi+i @r%ia &ri" l&' #i )bserva+i *' &'%r'+elele a&ar !l% !ai !ari. "$e&'r%a+i le"%ila $e @r%ie &@"' *@"$ i!a(i"ea es%e /"*' f)*ali0a%' $ar !'ri%' *@% !ai 18
!l% &)sibil. 3e%er!i"a+i $e *@%e )ri !'re#%e le"%ila; "!'r@"$ *@%e &'%r'+ele s"% *)"+i"%e /"%r" &'%r'+el !'ri% ve0i i!a(i"ea $e !ai D)s7. " *a0l l&ei $i" i!a(i"e; ea !'re#%e es%e $e )ri. %erinţe
a7. 3e%er!i"a+i (r)sis!e"%l l&ei $i" lab)ra%)r? b7. Cal*la+i &%erea )&%i*' a l&ei? *7. Cal*la+i $is%a"+a f)*al'? $7. S*rie+i re0l%a%ele /" %abel? e7.C)!&ara+i val)area )b+i"%' a $is%a"+ei f)*ale * val)area $e 5 *! &e *are ) are le"%ila7 #i s&"e+i *are ar fi &)sibilele srse $e er)ri; /" *a0l /" *are exis%' $ifere"+e /"%re *ele $)' val)ri. f7. Privi+i &a(i"a "ei *'r+i &ri" le"%il'; /"$e&'r%@"$ #i a&r)&ii"$ le"%ila $e &a(i"'. I!a(i"ile #i li%erele /#i s*i!b' $i!e"si"ea; /" f"*+ie $e $is%a"+a le"%ilei $e &a(i"'. Observa+i *' i!a(i"ile s"% *lare "!ai $a*' s*risl es%e /"%re $is%a"+a f)*al' a le"%ilei #i le"%il' i!a(i"ea va fi vir%al'; !'ri%' #i "er's%r"a%'. ....................................................................................................................................................... ....................................................................................................................................................... ....................................................................................................................................................... ....................................................................................................................................................... &
= &/0(2)
f = 1/
f
5 *! 'valuarea activităţii elevilor
N!ele elevliG elevil)r (r&ei
Reali0area *eri"+ei a7. &"*%e7
Reali0area *eri"+el)r b7; *7; $7 &"*%e7
Reali0area *eri"+el)r e7; f7 2 &"*%e7
N)%a fi"al'
19
CAPITOUL II. Mec!nic II.'. Determin!re! con%t!ntei e#!%tice ! unui re%ort
Scopul experimentului" $e%er!i"area *)"s%a"%ei elas%i*e a "i res)r%?
⃗
#eoria lucrării" H)r+a elasi*' / es%e f)r+a *e a&are a&are /"%r-" *)r& $ef)r!a% elas%i*. Ea se )&"e $ef)r!'rii iar val)area ei "!eri*' es%e $ire*% &r)&)r+i)"al' * $ef)r!area
⃗
&r)$s' /. ⃗
⃗
=
*
⃗⃗
∆ "$e
⃗
⃗⃗⃗
l = l – l 0 =+ , −
⃗⃗⃗
=− ∆ , - = * + ,* =
l
l 0
$ateriale necesare S&)r%; ri(l'; res)r%; (re%'+i * *@rli(? $od de lucru Se reali0ea0' !)"%aDl $i"
i!a(i"ea $e !ai D)s. Se /"re(is%rea0' &)0i+ia i"i+ial' a s*alei (ra$a%e #i a&)i se a(a+' &e r@"$; (re%'+i $e !ase *")s*%e. Se $e%er!i"'; &e"%r fie*are (re%a%e /" &ar%e; al"(irea res)r%li #i se %re* val)rile /" %abel. La fi"al la+i %)a%e (re%'+ile #i verifi*a+i $a*' l"(i!ea i"i+ial' a res)r%li es%e a*eea#i * *ea !'sra%' /"ai"%e $e a%@r"area (re%'+il)r se verifi*' $a*' res)r%l a r'!as /" $)!e"il $e elas%i*i%a%e $&' a*+i"ea f)r+ei $ef)r!a%)are7.
%erinţe a7. Reali0a+i ex&eri!e"%l #i *)!&le%a+i %abell $e !ai D)s? b7. Trasa+i (rafi*l $e&e"$e"+ei $e al"(ire a f)r+ei $ef)r!a%)are. Nr. *et. '.
. Eg/
- =&
N/
+ m/
*= -/+ #N/m$
- #N$
+. 3. :.
+#m$ 20
II.+. Determin!re! coeficientu#ui *e frec!re #! !#unec!re
⃗
Scopul experimentului $e%er!i"area *)efi*ie"%li $e fre*are $i"%re " *)r& #i &la"l /"*li"a% &e *are al"e*' "if)r!? #eoria lucrării H)r+ele $e fre*are a&ar la s&rafe+ele $e *)"%a*% $i"%e $)' *)r&ri. H)r+a $e fre*are la al"e*are " $e&i"$e $e !'ri!ea s&rafe+el)r afla%e /" *)"%a*%; *i $e "a%ra
s&rafe+el)r afla%e /" *)"%a*%; &ri" *)efi*ie"%l $e fre*are .. H)r+a $e fre*are es%e $ire*% &r)&)r+i)"al' * re0l%a"%a f)r+el)r *e a*+i)"ea0' &e $ire*+ia ")r!al' la $ire*+ia $e&las'rii f)r+' $e a&'sare7 - f = - n. Pe"%r " *)r& si%a% &e " &la" /"*li"a%; *e se $e&lasea0' $)ar sb &r)&ria (re%a%e; f)r+a $e a&'sare ")r!al' es%e *)!&)"e"%a (re%'+ii &e $ire*+ia &er&e"$i*lar' &e &la". 3a*' !i#*area es%e "if)r!' ⃗
⃗
⃗⃗⃗
5 ⃗
- f = & sin & n = & sin & cs = & sin
⃗
se "!e#%e ung,i *e frec!re7 $ateriale necesare" s&)r% &e"%r &la" /"*li"a%; &la" /"*li"a%; *er* ()"i)!e%ri*; &la" $e fre*are? = tg
$od de lucru Se asa!blea0' &la"l /"*li"a% *a /" i!a(i"ea $e !ai D)s. Se !'re#%e "(il &la"li *@%e &+i" as%fel /"*@% s' (asi! /"*li"area &e"%r *are *)r&l al"e*a &e &la" "if)r!. La fie*are /"*er*are; *i)*'"i! #)r &e &la" &e"%r a /"vi"(e /"+e&e"ireaJ
.Abia $&' a*eea; $a*' *)r&l " /"*e&e s' al"e*e; !'ri! $i" ") "(il f)ar%e &+i". C@"$ a! (asi% &)0i+ia &la"li &e"%r *are *)r&l *)b)ar' "if)r!; &)0i+i)"'! *er*l ()"i)!e%ri* as%fel /"*@% s' fie #)r s' !'sr'! "(il $e /"*li"a+ie a &la"li.
b)
%erinţe a7 Reali0a+i !)"%aDl; !'sra+i "(il $e fre*are a&)i *)!&le%a+i /" %abel? Rela+i ex&eri!e"%l; fix@"$; $e $a%a a*eas%a; ) (re%a%e &es%e *)r&l $e fre*are.
Par*r(e+i a*eia#i &a#i *a !ai /"ai"%e?*7 C)!&ara+i *ele $)' re0l%a%e )b+i"%e #i *)!e"%a+i = tg Nr d!t
sin
cs
*a0l 1 *a0l 2 21
II.3. Determin!re! r!n*!mentu#ui unui p#!n Fnc#in!t
Scopul experimentului $e%er!i"area ra"$a!e"%li "i &la" /"*li"a% /" *a0l ri$i*'rii "if)r!e; &ri" al"e*are; a "i *)r& s)li$? #eoria lucrării Ra"$a!e"%l "i &la" /"*li"a% es%e ra&)r%l $i"%re l*r !e*a"i* %il #i l*rl !e*a"i* *)"s!a%. L*rl !e*a"i* %il es%e l*rl !e*a"i* efe*%a% &e"%r ri$i*area "if)r!'; f'r' fre*are; a *)r&li la ) /"'l+i!e . L*rl !e*a"i* *)"s!a% es%e l*rl !e*a"i* efe*%a% &e"%r ri$i*area *)r&li la a*eea#i /"'l+i!e; $ar /" &re0e"+a fre*'ril)r.
==
∙
∙
" *a0l !i#*'rii "if)r!e Pe"%r *)r&l m2 ⃗ ⃗
l
= & 2
= m2 g
⃗
⃗
=0
3ar = &e"%r
*' firl are !as' "e(liDabil'. Ra"$a!e"%l s*ri&e%eli es%e
⃗
m1
h
⃗
f)ar%e !are; re0l%' = m2 g
m2
⃗ ⃗
⃗
Ra"$a!e"%l &la"li /"*li"a% se &)a%e s*rie
⃗⃗⃗
= ∙
$ateriale necesare &la" /"*li"a% $e "(i variabil; s&&)r% &e"%r &la" /"*li"a%; $i"a!)!e%r; *)r& &araleli&i&e$i*; ri(l'; s*ri&e%e &e"%r &la" /"*li"a%; (re%'+i $e !ase *")s*%e; *@rli( &e"%r (re%'+i? $od de lucru Se !'s)ar' (re%a%ea *)r&li &araleli&i&e$i* & 1 * $i"a!)!e%rl; a&)i
l"(i!ea l $ #i /"'l+i!ea $ &la"li. Se asa!blea0' &la"l /"*li"a%; !)"%@"$-se s*ri&e%ele &e"%r &la" /"*li"a%; *a /" i!a(i"ea $e !ai D)s. Se a#a0' *)r&l &e &la" #i se %re*e &es%e s*ri&e%e firl *e lea(' *)r&l &araleli&i&e$i*. La *a&'%l li se lea(' *@rli(l $e !as' *")s*%' #i se &" (re%'+i * !ase *")s*%e &@"' *e *)r&l m1 /"*e& s' r*e a&r)xi!a%iv "if)r! &e &la". 3e fie*are $a%' *@"$ se !ai &"e ) (re%a%e &e *@rli(; se *i)*'"e#%e #)r &e &la". Se
*al*lea0' !asa *)r&li m2 a$"@"$ !asele (re%'+il)r $i" *@rli( * *ea a *@rli(li7. Se %re* val)rile /" %abel. Se fa* !ai !l%e $e%er!i"'ri; &r)*e$@"$ la fel $e fie*are $a%'. 22
Nr.*et.
& 1 N/
l m/
m2 g/
m/
& 2 N/
" /
"c G/
'. +. 3. :.
%erinţe
a7.Reali0a+i ex&eri!e"%l $es*ris #i *)!&le%a+i %abell $e !ai ss? b7.Rela+i ex&eri!e"%l &e"%r al% "(i al &la"li /"*li"a% #i *)!&ara+i val)rile ra"$a!e"%el)r )b+i"%e /" *ele $)' *a0ri. N)%a+i ")ile val)ri )b+i"%e /" %abell $e !ai D)s
Nr.*et.
& 1 N/
m/
l m/
m2
& 2
"
g/
N/
/
"c
/
'. +. 3. :.
'valuarea activităţii elevilor
P"*%aD &e"%r *eri"+a a7. N!ele elevliG elevil)r (r&ei
1
2
3
2 &*%.7
1;5 &*%.7
1&*%.7
P"*%aD &e"%r *eri"+a b7. 1
2&*%.7
2
3
1;5&*%7 1&*%.7
N)%a fi"al'
1- Reali0area !)"%aDli ? 2-Efe*%area !'sr'%)ril)r #i %re*erea val)ril)r /" %abel? 3-
Efe*%area *al*lel)r. 23
II.:. . P!r!#e#ogr!mu# for-e#or
Scopul experimentului" $e%er!i"area re0l%a"%ei a $)' f)r+e * a*ela#i &"*% $e a&li*a+ie? #eoaria lucrării" Re0l%a"%a a $)' f)r+e * a*ela#i &"*% $e a&li*a+ie es%e f)r+a re&re0e"%a%' $e $ia()"ala &aralel)(ra!li *e are *a la%ri *ele $)' f)r+e. ⃗⃗ ⃗
⃗⃗⃗ +
=
sa - 1c/s
1
√
"$e
+
+
1
2
- 2c/s
2
iar =
5
$ateriale necesare s&)r% ; $i"a!)!e%r; (re%'+i $e !ase
*")s*%e; fir ; *er* ()"i)!e%ri*; 2 s*ri&e+i; %abele !a%e!a%i*e? - 1
1
$od de lucru Se reali0ea0' !)"%aDl $i" fi(ra "r. 1.; $e !ai
2
- 2
D)s #i se &" (re%'+i la *a&e%ele *el)r $)' fire &e"%r a se reali0a e*ilibrl. =re%a%ea !asel)r $i" &ar%ea s%@"(' va fi - 1 iar (re%a%ea !asel)r $i" &ar%ea $rea&%' va fi - 2. Se *i%es* val)rile "(iril)r 2
1
#i
; a&)i se %re* $a%ele /" %abel. Se *al*lea0' val)area re0l%a"%ei
* aD%)rl f)r!lei $e *)!&"ere a f)r+el)r #i se *)!&ar' * val)area f)r+ei 5 ; i"$i*a%' $e $i"a!)!e%r. Se *)!&le%ea0' %abell $e !ai D)s. 5 - 1
Se reali0ea0' !ai !l%e !'sr'%)ri; &e"%r $iferi%e val)ri ale f)r+el)r
#i - 2 #i &e"%r $iferi%e val)ri ale "(iril)r $i"%re f)r+ele - 1 #i - 2. Se *)!&ar' $e fie*are
$a%' val)area *al*la%' a re0l%a"%ei * val)area *i%i%' &e $i"a!)!e%r Nr d!t ' + 3 :
. 1 #*g$
- 1 & 1 m 1 g m2 #*g$ #N$
- 2 & 2 m 2 g #N$
1
2
- 1c/s
1
#N$
- 2c/s
2
5 #N$
O al%' varia"%' &e"%r &"erea /" evi$e"+' a &aralel)(ra!li f)r+el)r es%e ils%ra%' /" fi(ra "r.2. " a*es% !)"%aD; val)area f)r+el)r se &)a%e *i%i $ire*% * aD%)rl $i"a!)!e%rel)r. "*er*a+i #i a*eas%' varia"%'
4i!ura nr.+
4i!ura nr.* 24
II.<. Ec,i#i&ru# unui corp %u& !c-iune! unui %i%tem *e for-e
Scopul experimentului" a"ali0a efe*%el)r a&li*'rii "i sis%e! $e f)r+e as&ra "i )bie*% #i s%$ierea *)"$i+iil)r $e e*ilibr? #eoria lucrării" U" *)r& afla% /" re&as ⃗9 #i ⃗9 7 es%e /" e*ilibr s%a%i*. Cele $)' *)"$i+ii *are %rebie sa%isf'*%e &e"%r *a " *)r& s' se afle /" e*ilibr s"%
⃗ ∑⃗ = ⃗ E*ilibr $e %ra"sla+ie Re0l%a"%a %%r)r f)r+el)r ex%er"e *are a*+i)"ea0' as&ra *)r&li es%e "l'. =
Eclibru de rotţ ie: Moentul rezultnt l tuturor oentelor foţ elor externe ce cţ ioneză supr corpului este nul ∑ ⃗⃗ !entru un corp "n ecilibru de trnslţie# dc ă
⃗
= fa+' $e " a"!i% &"*%; a%"*i es%e 0er) fa+'
.
$e )ri*e &"*% $i" sis%e!l $e referi"+'. - r
%
$i"%re ve*%)rl $e &)0i+ie ⃗al &"*%li $e a&li*a+ie al
6
⃗ ⃗
=
⃗
f)r+ei*are a*+i)"ea0' as&ra *)r&li; fa+' $e *e"%rl $e r)%a+ie #i f)r+'
⃗ ×
. - r sin
M)!e"%l f)r+ei se ex&ri!' &ri" &r)$sl ve*%)rial
⃗ "$e
es%e"(il $i"%reve*%)rii #i⃗ .3ar r sin
6
. - 6
C)"ve"+ii $e se!" a$)&%a%e; &e"%r ab)r$area &r)ble!el)r $e e*ilibr 1. T)a%e f)r+ele /"$re&%a%e /" se"sl &)0i%iv al axel)r Ox #i OQ se *)"si$er' &)0i%ive; iar *ele )rie"%a%e /" se"s i"vers; "e(a%ive? 2. M)!e"%l f)r+ei fa+' $e " &"*% *are $e%er!i"' r)%irea s&re $rea&%a /" se"sl a*el)r $e *eas)r"i*7; /l *)"si$er'! &)0i%iv #i *el s&re s%@"(a /" se"s %ri()")!e%ri*7 "e(a%iv. C)"si$er'! &)0i%iv #i *el s&re s%@"(a /" se"s %ri()")!e%ri*7 "e(a%iv. $ateriale necesare Tabla !a("e%i*a; %iD' * ('ri; $e !as' *")s*%'; fir; (re%'+i $e !ase *")s*%e; 2 s*ri&e+i; s&)r%ri !a("e%i*e &e"%r s*ri&e%i? Ap#ic!ti! nr.'?E)emp#uH
$od de lucru Le(a+i ) %iD'; la *a&e%e; * 2 fire $e a+' #i %re*e+i firele &es%e s*ri&e+i; *a /" fi(ra $e !ai D)s. A('+a+i; la *a&e%e firel)r; (re%'+i as%fel /"*@% %iDa s' fie /" e*ilibr s%a%i* %iDa are 129 (7. N)%a+i !asele (re%'+il)r. 3ese"a+i f)r+ele *e a*+i)"ea0' as&ra %iDei; a&)i
s*rie+i bra+ele f)r+el)r /" f"*+ie $e $is%a"+a $i"%re $)' ('ri ex b15a7; *)"si$er@"$ *a 25
&"*% $e referi"+' *e"%rl $e (re%a%e al %iDei si%a% la !iDl)*l ei7; O. S*rie+i e*a+iile $e e*ilibr; +i"@"$ *)"% $e *)ve"+iile $e se!" #i verifi*a+i $a*' s"% /"$e&li"i%e a*es%e *)"$i+ii ; /"l)*i$ val)rile "!eri*e ale f)r+el)r.
a O
m1= 60 g.
m2= 60 g.
1. C)"$i+ia e*ilibrli $e %ra"sla+ie se s*rieL F 1
"' "+ @ Gt 5 7
F 2 a
:erifi*area *)"$i+iei
O
m' g m+ g @ mt g 5 7 797=g 797=g @ 79'+g 5 7
C)"$i+ia e*ilibrli $e %ra"sla+ie es%e /"$e&li"i%'.
G
2. C)"$i+ia e*ilibrli $e r)%a+ie se s*rie "' &' @ "+ &+ @ Gt 7 5 7 :erifi*area *)"$i+iei 797=g
D)s; !ai i"%@i %e)re%i*; a&)i ex&eri!e"%al.
a O
m1= 120 g.
m3= 60 g.
m2= 60 g.
26
a
O
C)"$i+ia e*ilibrli $e %ra"sla+ie................................................................................................. :erifi*area *)"$i+iei e*ilibrli $e %ra"sla+ie........................................................................... C)"$i+ia e*ilibrli $e r)%a+ie.................................................................................................... :erifi*area *)"$i+iei e*ilibrli $e r)%a+ie................................................................................ Ap#ic!-i! nr.3H Reve"i+i la *)"fi(ra+ia sis%e!li $e la a&li*a+ia "r.1; $e&'r%a+i s*ri&e+ii
"l fa%' $e *el'la%; &e $ire*+ie )ri0)"%al'; res%abili+i e*ilibrl sis%e!li #i rela+i &r)*e$ra $e verifi*are a e*a+iil)r.
a O
m1= 70 g.
m2= 70 g.
a
O
C)"$i+ia e*ilibrli $e %ra"sla+ie............................................................................................. :erifi*area *)"$i+iei e*ilibrli $e %ra"sla+ie........................................................................ C)"$i+ia e*ilibrli $e r)%a+ie................................................................................................ :erifi*area *)"$i+iei e*ilibrli $e r)%a+ie............................................................................. 27
II.=. Re#!-i! *intre greut!te! unui corp $i m!%! %!
Scopul lucrării" $e%er!i"area ex&eri!e"%al' a rela+iei $i"%re (re%a%ea #i !asa "i *)r& ? #eoria lucrării 3@"$ $r!l "i *)r& afla% la ) m
/"'l+i!e )are*are fa+' $e &)$ea; el va *'$ea liber sb a*+i"ea (re%'+ii sale. " vi$; %)a%e *)r&rile *a$ * a*eea#i
⃗
⃗
a**elera+ie; a**elera+ia (ravi%a+i)"al'; . =re%a%ea "i *)r& es%e f)r+a * *are P'!@"%l a%ra(e *)r&l. Ea es%e )rie"%a%' ver%i*al; /" D)s; s&re *e"%rl P'!@"%li. H)r+a *are $ef)r!e0' " $i"a!)!e%r a%"*i *@"$ es%e " *)r& 7m8ntl
ss&e"$a% la *a&'%l a*es%ia; es%e (re%a%ea. $ateriale necesare $i"a!)!e%r; *@rli( $e !as'
*")s*%'; $is*ri $e !ase *")s*%e; s&)r% &e"%r $i"a!)!e%r? $od de lucru" &"e! $i"a!)!e%r /"
s&)r%; a&)i a('+'! *@rli(l la *a&'%l a*es%ia. P"e! " $is* &e *@rli(. Cal*l'! !asa a('+a%' $e $i"a!)!e%r #i ) %re*e! /" %abel a$"@"$ !asa *@rli(li * !asa $is*li7. Ci%i!
i"$i*a+ia
*)res&"0'%)are
a
$i"a!)!e%rli; %re*@"$ (re%a%ea sis%e!li /" %abel . Cal*l'! ra&)r%l $i"%re (re%a%e #i !asa *)r&li. Re&e%'! &r)*e$ra; !'ri"$ !asa sis%e!li $e la *a&'%l $i"a!)!e%rli. Nrd!t
1
2
3
4
)
m #*g$
&#N$ (
)
"%reb'ri a7. C *e !'ri!e fi0i*' se &)a%e i$e"%ifi*a ra&)r%l GmF......................................................... b7. Ce e*a+ie !a%e!a%i*' se &)a%e s*rie /"%re G #i mF ............................................................. *7. S*rie+i ve*%)rial e*a+ia ('si%' la &"*%l b7......................................................................... 28
II.. Determin!re! !cce#er!-iei gr!(it!-ion!#e cu !Jutoru# pen*u#u#ui
gr!(it!-ion!#
Scopul experimentului $e%er!i"area ex&eri!e"%al' a a**elera+iei (ravi%a+i)"ale * aD%)rl &e"$lli (ravi%a+i)"al? #eoria lucrării Pe"$ll (ravi%a+i)"al es%e al*'%i%
$i"%r-) sfer' !i*' $e !asa !; ss&e"$a%' $e " fir i"ex%e"sibil #i f)ar%e #)r. 3e&lasa% la%eral #i l'sa% a&)i liber T
&e"$ll )s*ilea0'. H)r+a $e rea$*ere /" &)0i+ia $e e*ilibr
#
es%e *)!&)"e"%a %a"(e"+ial' a (re+'%ii; *ealal%' *)!&)"e"%' a (re%'+ii sferei av@"$ *a efe*% $)ar %e"si)"area firli.
Gt
Gt 5 G 2 %in K 5 m 2 g 2 %in K Pe"%r )s*ila+ii !i*i; * 0 5
Gn
sb 9;9 ra$7; $i" %abelele !a%e!a%i*e se )bserv' *' %in K G
K #i $e*i &%e! s*rie Gt m 2 g 2 K 5 m 2 g 2 ) #
Observ'! *' f)r+a $e reve"ire es%e $ire*% &r)&)r+i)"al' * $e&'r%area $e &)0i+ia $e e*ilibrJ x7; $e*i &)a%e fi *)"si$era%' *a ) f)r+a *vasielas%i*';$a*a ")%'! 5 m2g # #i $e*i # 2p
m m l 2p 2p m! 5 ! l
∙ ∙
=
$ateriale necesare" s%a%iv; &e"$le (ravi%a+i)"ale $e l"(i!i $iferi%e 25 *!; 9 *!;
59 *!.; 49 *!7; *r)")!e%r; *al*la%)r $e b0"ar. $od de lucru Se !'s)ar' l"(i!ea &e"$lli; l. Se &"e &e"$ll /" !i#*are; av@"$
(riD' *a "(il $e $evia+ie s' fie !i*. Se *r)")!e%rea0' /"%r-" i"%erval $e %i!& %; "!'rl $e )s*ila+ii *)!&le%e; ". Se *al*lea0' val)area &eri)a$ei; se %re* val)rile /" %abel #i se *al*lea0' a**elera+ia (ravi%a+i)"al' (. Se re&e%' &r)*e$ra * &e"$le $e l"(i!i $iferi%e #i se fa*e !e$ia ari%!e%i*' a %%r)r val)ril)r a**elera+iei (ravi%a+i)"ale )b+i"%e. Nr :!t
n
g
%/
o%ci#!-ii/
%/
m% /
+
+
m% /
' + 3 :
29
CAPITOLUL III. "enomene termice III.'. Stu*iu# !me%tecu#ui ! *ou #ic,i*e cu temper!turi *iferite
Scopul experimentului $e%er!i"area %e!&era%rii fi"ale a "i a!es%e* $e $)' *a"%i%'+i $iferi%e ale a*elia#i li*i$; * %e!&era%ri $iferi%e? #eoria lucrării C)"f)r! e*a+iei *al)ri!e%ri*e; la a!es%e*l a $)' li*i$e; *'l$ra *e$a%' $e *)r&l !ai *al$ es%e e(al' * *'l$ra &ri!i%' $e *)r&l !ai re*e. E*a+ia se &)a%e s*rie ;c!dat = ;
;c a
m1 ca #t 1
$ m2 ca #
t 2 $
+
$ateriale necesare" %rei vase (ra$a%e; "l !are #i $)' !ai !i*i; $)' %er!)!e%re; bala"+' ele*%r)"i*'? $od de lucru se a#a0' "l $i" vasele !i*i; ()l; &e bala"+'; #i se !'s)ar' !asa li. Se
%)ar"' /" el a&' la %e!&era%ra *a!erei. Se !'s)ar' !asa vasli &li"; se fa*e $ifere"+a #i se %re*e /" %abel !asa a&ei la %e!&era%ra *a!erei m2 $. Se &"e $e)&ar%e vasl. Se re&e%' &r)*e$ra &e"%r vasl * a&' fierbi"%e #i se $e%er!i"' #i !asa a&ei fierbi"+i m17. Se *i%es* i"$i*a+iile %er!)!e%rel)r #i se %re* val)rile /" %abel. Se %)ar"' *ele $)' *a"%i%'+i $e a&' /" vasl !are #i se i"%r)$*e %er!)!e%rl *are a s%a% /" a&a re*e /" vas. A%e"+ie E "e*esar s' se l*re0e re&e$e; &e"%r *a &ier$erile $e *'l$r' $i" %i!&l ex&eri!e"%li; s' " i"fle"+e0e f)ar%e !l% re0l%a%ele a*es%ia; iar er)rile s' fie !i*i7 C@"$ "ivell !er*rli $i" %er!)!e%r a /"*e%a% s' !ai *reas*' se *i%e#%e %e!&era%ra a!es%e*li. Se %re* $a%ele /" %abel #i se fa* *al*lele. Se *)!&ar' %e!&era%ra $e e*ilibr afla%' &e *ale %e)re%i*' * %e!&era%ra $e%er!i"a%' &ri" ex&eri!e"%. . 1
m2
t 1
t 2
calc
!+
g/
g/
8C/
8C/
8C/
+
8C/
'valuarea activităţii elevilor
N!ele elevliG (r&ei
Reali0area ex&eri!e"%li 5 &"*%e7
Ci%irea $a%el)r ex&eri!e"%ale 2 &"*%e7
Cal*ll li calc
2 &"*%e7
30
III.+. Stu*iu# fier&erii !pei #! pre%iune !tmo%feric norm!#
Scopul experimentului" $e%er!i"area &"*%li $e fierbere a a&ei la &resi"e a%!)sferi*' ")r!al'? #eoria lucrării Hierberea /"sea!"' va&)ri0are /" %)a%' !asa sbs%a"+ei. " li*i$e se
('se#%e aer $i0)lva% #i; /!&re"' * va&)rii sa%ra+i; f)r!ea0' ble la )ri*e %e!&era%r'. O$a%' * *re#%erea %e!&era%rii; *re#%e #i &resi"ea va&)ril)r sa%ra+i #i blele s"% (e"era%e /" %)% v)l!l $e li*i$. La ) a"!i%' %e!&era%r'; blele aD"( la s&rafa+a li*i$li #i se s&ar(; %e!&era%ra r'!@"e *)"s%a"%'; a*es%a fii"$ !)!e"%l fierberii. Te!&era%ra *)"s%a"%' a va&)ril)r $i" i!e$ia%a ve*i"'%a%e a li*i$li se "!e#%e %e!&era%r' $e fierbere. Te!&era%ra $e fierbere $e&i"$e $e "a%ra sbs%a"+ei #i $e &resi"ea sb *are se reali0ea0' fierberea. La &resi"e a%!)sferi*' ")r!al' %e!&era%ra $e fierbere es%e ) *)"s%a"%' $e !a%erial; fii"$ " *ri%eri $e verifi*are a &ri%'+ii sbs%a"+el)r. Hierberea /"*e&e a%"*i *@"$ &resi"ea va&)ril)r sa%ra+i $evi"e e(al' * &resi"ea $e $eas&ra li*i$li. $ateriale necesare b%elie $e (a0 * ar0'%)r; si%' * !iDl)* $e *era!i*'; &aar (ra$a%; a&'; %er!)!e%r * !er*r; s&)r% "iversal * *le!'; *eas. $od de lucru Se reali0ea0' !)"%aDl $i" i!a(i"e; se &" 159 !l a&' /" &aar; se /"*e&e /"*'l0irea a&ei $i" &aar #i se *i%e#%e i"$i*a+ia %er!)!e%rli $i" !i"% /" !i"%; &@"' *@"$ a&a fierbe /" %)a%' !asa sa. Se %re* val)rile /" %abel. ''7 8C '77 67 7 7 =7 <7 :7 37 +7 '7 7
min.
'
+
3
:
<
=
6
%erinţe A"ali0a+i (rafi*l #i s&"e+i *are e %e!&era%ra $e fierbere a a&ei la &resi"e a%!)sferi*' ")r!al'. ……………………………………………………………………........ 31
III.3. Stu*iu# fier&erii !pei %u& ni(e#u# pre%iunii !tmo%ferice norm!#e
Scopul experimentului es%e $e a ar'%a; $i" &"*% $e ve$ere *ali%a%iv; !)$l /" *are a&a &)a%e s' fiarb' la ) %e!&era%r' sb 199KC; a%"*i *@"$ &resi"ea es%e sb "ivell &resi"ii a%!)sferi*e. #eoria lucrării" Hierberea /"*e&e a%"*i *@"$ &resi"ea va&)ril)r sa%ra+i $evi"e e(al' * &resi"ea $e $eas&ra li*i$li. La al%i%$i"i !ari; a*)l) "$e &resi"ea es%e s*'0%'; s-a *)"s%a%a% *' %e!&era%ra $e fierbere s*a$e. $ateriale necesare vas $e fil%rare; %er!)!e%r * !er*r; 1 $)& $e *a*i* * )rifi*i &e"%r %er!)!e%r; 1 $)& si!&l; $e *a*i*; &e"%r )rifi*il la%eral al vasli $e fil%rare; si%'
* !iDl)* *era!i*; b%elie * ar0'%)r; !'"#' %er!)i0)la"%' &e"%r !a"evrarea vasli fierbi"%e sa *le!' * %iD'7. $od de lucru" P"e+i 159 !l $e a&' s' fiarb' /" vasl $e fil%rare. A#%e&%a+i 5 !i"%e $&' *e se a%i"(e &"*%l $e fierbere. "%re %i!&; &re('%i+i $)&l $e *a*i* * %er!)!e%rl a#a *! es%e ils%ra% /" $ese"l r!'%)r. 3a*' %er!)!e%rl " i"%r' /" )rifi*il $)&li; "(e+i-l * &+i"' vaseli"'. "*i$e+i vasl $e fil%rare * $)&l $e *a*i* * %er!)!e%r. "*i$e+i #i )rifi*il la%eral al vasli $e fil%rare * " $)& !ai !i*; f'r' )rifi*i.. H)l)si"$ *le!a sa !'"#a; /"*li"a+i vasl $e fil%rare &e"%r a !e0i blbl %er!)!e%rli. S&'la+i vasl $e fil%rare * a&' re*e #i )bserva+i *! /"*e&e $i" ")s ' fiarb'. Ci%i+i i"$i*a+ia %er!)!e%rli #i ")%a+i t fi!r6!r! =……………... 'xplicaţie" " %i!&l fierberii; va&)rii ar"*' aerl $eas&ra a&ei. 3&' *e a+i /"*is vasl #i l-a+i s&'la% * a&' re*e; va&)rii $i" i"%eri)r se
*)"$e"sea0'; re$*@"$ &resi"ea. :a&)rii &)% aD"(e la %e!&era%ra !e$ili; la ) &resi"e !ai !i*' $e*@% "ivell &resi"ii a%!)sferi*e. #ubul cu sfere pulsante A*es% $is&)0i%iv *)"s%' $i"%r-" %b /"(s% /"$)i% /" "(iri $re&%e la fie*are *a&'%; av@"$ $)' sfere !ari la *a&e%e. P@"' la D!'%a%e $i" %b es%e !&l% * a&' sa al*))l; sb vi$ #i si(ila%. i"e+i * ) !@"' "a $i"%re sferele %bli * sfere &lsa"%e #i
)bserva+i *e se /"%@!&l' * a&a $i" i"%eri)r Ex&li*a+i fe")!e"l. …………………………………………………………………… ………………………………………………………...................... .......................................................................................................... " a*es% *a0; %e!&era%ra $e fierbere es%e t fier&ere 5……………... 32
III.:. Determin!re! c!p!cit-ii c!#orice ! unui c!#orimetru
Scopul experimentului $e%er!i"area *a&a*i%'+ii *al)ri*e a "i *al)ri!e%r? #eoria lucrării Ca&a*i%a%ea *al)ri*' a "i *)r& es%e !'ri!ea fi0i*' "!eri* e(al' *
*'l$ra "e*esar' a*eli *)r&; &e"%r a-i varia %e!&era%ra * ) "i%a%e. = ∆
=
[]
. Ca&a*i%a%ea *al)ri*' ese ) *ara*%eris%i*' a fie*'ri *)r& /" &ar%e.
'
[]
[]
∙
Pe"%r a $e%er!i"a *a&a*i%a%ea *al)ri*' a "i *al)ri!e%r; i"%r)$*e! ) !as' a&r)xi!a%iv 599 !l7 $e a&' fierbi"%e /" *al)ri!e%rl afla% la %e!&era%ra *a!erei. A&a fierbi"%e va *e$a *'l$r' iar *al)ri!e%rl va &ri!i *'l$r'. E*a+ia *al)ri!e%ri*' es%e ;c!dat = ;
#
t c $ m a ca #t a
$
=
(
)
$ateriale necesare b%elie $e (a0 * ar0'%)r; si%' * !iDl)* *era!i*; *al)ri!e%r * a**es)rii; &aar (ra$a%; %er!)!e%r; !'"#' %er!)i0)la"%'. $od de lucru Se f)l)se#%e " *al)ri!e%r afla% la %e!&era%ra *a!erei; * %er!)!e%r încorporat (cu toate acceorii!e)" #e notea$% te&peratura indicat% de ter&o&etru! ca!ori&etru!ui (care ar trebui % e ea!% cu cea a ca&erei)" #e pune ap% întrun pa*ar radat (500 &!)" #e notea$% &aa apei în tabe! " #e pune apa !a ert i c,nd începe % arb%- e &%oar% te&peratura ei cu un ter&o&etru" .o!oind &%nua ter&oi$o!ant%- e pune i&ediat apa în ca!ori&etru- e aa$% capacu! i e ait%" #e ateapt% ec*i!ibru! ter&ic între ap% i ca!ori&etru (ca& 10 &in)" C,nd ni/e!u! &ercuru!ui din ter&o&etru nu &ai crete- e notea$% te&peratura de ec*i!ibru în tabe!" #e ac ca!cu!e!e" #e repet% procedura de 3 4 ori"
Nr. *et. '
c 8C/
ma Eg/
+
t a 8C/
8C/
/
ca G Eg M/
/
:'7
3
!git!tor termometru (!% interior (!% e)terior (!% e)terior Suport i;o#!tor
Aer
33
III.<. Determin!re! c#*urii %pecifice ! unui corp
+
Scopul experimentului $e%er!i"area *'l$rii s&e*ifi*e a "i *)r&? #eoria lucrării" C'l$ra s&e*ifi*' a "i *)r& es%e !'ri!ea fi0i*' "!eri* e(al' * *'l$ra necear% unit%ii de &a% dintrun corp au ubtan%- pentru ai /aria te&peratura cu o
"i%a%e.=
[] =
[]
∙∆
[]∙[]
C'l$ra s&e*ifi*' ese ) *ara*%eris%i*'
' ∙
$e !a%erial. Pe"%r a $e%er!i"a *'l$ra s&e*ifi*' a "i *)r& $e !as' !; f)l)si! *al)ri!e%rl. I"%r)$*e! *)r&l fierbi"%e /" *al)ri!e%rl /" *are exis%' $eDa a&' la %e!&era%ra *al)ri!e%rli. C)r&l fierbi"%e va *e$a *'l$r' iar a&a #i *al)ri!e%rl v)r &ri!i. E*a+ia *al)ri!e%ri*'; ;c!dat = ;
−)
( −
$ ma ca #
t a $
#
t a $
)
$ateriale necesare" *al)ri!e%r * a**es)rii a *'ri *a&a*i%a%e *al)ri*' ) *")a#%e!. " *a0l *al)ri!e%rli $i" i!a(i"e; C 8;4 VG>7; bala"+'; &aar (ra$a%; *)r& !e%ali*; %er!)!e%r. $od de lucru Se &"e /" *al)ri!e%r ) !as' $e a&' a&r)xi!a%iv 99 !l7. Se &"e
*a&a*l *al)ri!e%rli #i se las' *a *ele $)' s' aD"(' la e*ilibr %er!i*. "%re %i!& *@"%'ri! !asa *)r&li $e *&r mc7 ; %re*e! val)area /" %abel #i /l a#e0'! /"%r-" &aar * a&' /" *are exis%' " %er!)!e%r; &"@"$-l la /"*'l0i%. C@% %i!& se /"*'l0e#%e *)r&l; !'sr'! %e!&era%ra a&ei #i a *al)ri!e%rli; *i%i"$ i"$i*a+ia %er!)!e%rli $i" *al)ri!e%r 7. N)%'! val)area /" %abel. C@"$ a&a $i" &aar fierbe; *i%i! i"$i*a+ia %er!)!e%rli $i" &aar t c7; ) ")%'! /" %abel #i l'! *)r&l $i" &aar; * aD%)rl "i *le#%e $e le!" &"@"$-l i!e$ia% /" *al)ri!e%r. P"e! *a&a*l #i a(i%'! * aD%)rl a(i%a%)rli. Ur!'ri! i"$i*a+ia %er!)!e%rli $i" *al)ri!e%r. C@"$ sis%e!l aD"(e la e*ilibr a&r)xi!a%iv 19 !i".7 ; "ivell !er*rli $i"
%er!)!e%rl *al)ri!e%rli " !ai *re#%e #i se *i%e#%e %e!&era%ra $e e*ilibr
" #e notea$% în
tabe! i e ac ca!cu!e!e"
. a g/
mc g/
t a 8C/
t c 8C/
8C/
ca G Eg M/
/
cc G Eg M/
G Eg M/
:'7
34
CAPITOLUL IV. E#ectricit!te $i m!gneti%m IV.'. Uti#i;!re! mu#timetru#ui
Ml%i!e%rl $i(i%al es%e ) varia"%' !)$er"' a !l%i!e%rli *lasi*; reali0ea0' ) i!&e$a"+' f)ar%e !are &e s*ala %e"si"il)r W % 19 M&G:7; f)l)si"$ a!&lifi*a%)are $e *re"% *)"%i" &erf)r!a"%e; r!a%' $e ) *)"versie a"al)(-"!eri*' a se!"alel)r !'sra%e #i ) afi#are a re0l%a%li &e !i"i!! %rei *ifre /"s)+i%e $e se!" sa . 3e )bi*ei s"% &rev'0%e * a%)-s*alare ale(ere a $)!e"ili $e l*r7; *eea *e le *)"fer' ) !are #ri"+' /" r!'rirea %e"si"il)r le"% variabile. Pre*i0ia $e *i%ire a val)ril)r $e *re"% aD"(e la 1 0⁄00 . Ali!e"%area a*es%)r !l%i!e%re se fa*e $e re(l' la " a*!la%)r $e :; /"*)r&)ra%. Afi#aDl * *ris%ale li*i$e i"$i*' !'ri!ea !'sra%'. Ml%i!e%rele $e l%i!' (e"era+ie &)% fi *)"e*%a%e * *al*la%)rl %ra"s!i+@"$ re0l%a%ele !'sr'%)ril)r. P)% !'sra !'ri!i fi0i*e &re*! %e"si"e ele*%ri*' *.a. #i *.a.7; i"%e"si%a%e a *re"%li ele*%ri* *.*. #i *.a.7; re0is%e"+a ele*%ri*'; %e!&era%r'; *a&a*i%a%e ele*%ri*'. C)"e*%area /" *ir*i% se fa*e %ili0@"$ $)' b)r"e; $i"%re *are "a es%e; /" !)$ )bli(a%)ri; b)r"a *)!"'; $ifere"+ia%' $e *elela%e b)r"e &ri" $esi("l !l%i!e%rli s&re exe!&l; /" *a0l !l%i!e%rli $i" i!a(i"e; b)r"a *)!"' es%e si"(ra *)l)ra%' /" "e(r; *elela%e fii"$ *)l)ra%e /" r)#7. Cealal%' b)r"' se ale(e /" f"*+ie $e !'ri!ea fi0i*' *are se !'s)ar'. Ca a!&er!e%r; se lea(' /" serie * &)r+i"ea $e *ir*i% &ri" *are se $)re#%e $e%er!i"are i"%e"si%'+ii *re"%li ele*%ri*. Ca v)l%!e%r; se lea(' /" &aralel * &)r+i"ea $e *ir*i% la *a&e%ele *'reia se $)re#%e !'srarea %e"si"ii ele*%ri*e. Domeniu# *e m%ur!re ! inten%it-ii c.c. Domeniu# *e m%ur!re ! inten%it-ii c.!. Born! pentru m%ur!re! int. curen-i#or pe%te ' A Born! pentru m%ur!re! int. curen-i#or %u& ' A
Domeniu# *e m%ur!re ! re;i%ten-ei e#ectrice Domeniu# *e m%ur!re ! ten%iunii c.c. Domeniu# *e m%ur!re ! ten%iunii c.!. Born! pt. m%ur!re! ten%iunii9 frec(en-ei %!u re;i%ten-ei Born! comun
35
IV.+. Uti#i;!re! unei %ur%e *e ten%iune
Pe"%r a f"*+i)"a; *ir*i%ele ele*%ri*e %rebie ali!e"%a%e ele*%ri*. Ele "e*esi%' $iferi%e %e"si"i #i *re"+i $&' f"*+iile &e *are le a #i /" f"*+ie $e *)!&)"e"%ele * *are s"% e*i&a%e. Pe"%r a f"*+i)"a *)re*%; srsa $e %e"si"e es%e s%abili0a%'; a$i*'; &e"%r " a"!i% $)!e"i $e varia+ie al %e"si"ii $e re+ea; al !)$ifi*'rii *)"s!li #i la s*i!barea %e!&era%rii a!bia"%e; %e"si"ea fr"i0a%' es%e &ra*%i* *)"s%a"%'. 3e )bi*ei $)!e"il $e varia+ie al %e"si"ii $e ie#ire es%e /"%re 9 : #i 9 :; iar al *re"%li $ebi%a% /"%re 9 A #i 5 A. 3e )bi*ei srsa $e %e"si"e f"*+i)"ea0' /" re(i! fl)%a"%J; a$i*' b)r"ele $e ie#ire s"% i0)la%e fa+' $e *ar*as' #i $e "ll $e &r)%e*+ie. A*eas%a &er!i%e *)"e*%area srsei /"%r-" &"*% al *ir*i%li !'sra% afla% $eDa la ) a"!i%' %e"si"e. 3e ase!e"ea &)lari%a%ea &)a%e fi aleas' /" )ri*e !)$ &ri" *)"e*%area a$e*va%' a b)r"el)r #i . Pe"%r a f)l)si *)re*% srsa $e %e"si"e %rebie s' se r!'reas*' :erifi*area %e"si"ii $e ali!e"%are la re+eaa $e 229 : #i exis%e"+a si(ra"+ei f0ibile &rev'0%' $e srs'? Se verifi*' *a *ir*i%l $e ie#ire s' fie *)"e*%a% *)re*%; $e re(l' es%e bi"e s' exis%e " /"%rer&'%)r &e *ir*i%l ali!e"%a% &e"%r a &%ea re(la %e"si"ea la ie#irea srsei #i a&)i s' se ali!e"%e0e *ir*i%l s%$ia%? Se ale(e %e"si"ea $e ie#ire &ri" re(larea b%)"li &)%e"+i)!e%ri* al srsei; r!'ri"$-se v)l%!e%rl &r)&ri sa " v)l%!e%r ex%eri)r; a&li*a% la b)r"e? 3&' ali!e"%area !)"%aDli s%$ia% se )bserv' *re"%l $ebi%a%; r!'ri"$-se /"s*rierea /" $)!e"il a$!is? 3a*' se )bserv' ) *re#%ere i!&)r%a"%' a i"%e"si%'+ii *re"%li sa s*'$erea %e"si"ii $e ie#ire fixa%e; /"sea!"' *' f"*+i)"area " es%e *)re*%' #i %rebie s' se $e*)"*%e0e srsa; &e"%r *a a&)i s' se *a%e *a0a.
Borne pentru !#iment!re c.!.
Domeniu# *e m%ur!re
Borne pentru Buton !#iment!re c.c. PORNITOPRIT
36
IV.3. Determin!re! re;i%ten-ei e#ectrice ! unei po-iuni *e circuit uti#i;n* (o#tmetru# $i !mpermetru#9 Fn circuite *e curent continuu
Scopul experimentului $e%er!i"area re0is%e"+ei ele*%ri*e a "ei &)r+i"i $e *ir*i%? #eoria lucrării Re0is%e"+a ele*%ri*' es%e ) !'ri!e fi0i*' * val)ri &)0i%ive; )
*ara*%eris%i*' ese"+ial' a *)"$*%)ril)r !e%ali*i; re&re0e"%@"$ &r)&rie%a%ea *)"$*%)ril)r $e a se )&"e %re*erii *re"%li ele*%ri*. 3e&i"$e $e $i!e"si"ile *)"$*%)rli; "a%ra !a%erialli $i" *are e al*'%i% #i $e %e!&era%ra a*es%ia. Re0is%e"+a ele*%ri*' a "i *)"$*%)r sa a "ei &)r+i"i $e *ir*i%7 se &)a%e $e%er!i"a ra&)%@"$ %e"si"ea la *a&e%ele &)r+i"ii $e *ir*i% la i"%e"si%a%ea *re"%li ele*%ri* *e ) s%r'ba%e. =
[ ] = [[] ] =
o,m/
$ateriale necesare" srs' $e D)as' %e"si"e; a!&er!e%r; v)l%!e%r; re0is%)r sa *ase%' * re0is%)ri7 * re0is%e"+' "e*")s*%'; *)"$*%)are ele*%ri*e $e le('%r' * fi#' ba"a"'. $od de lucru Se reali0ea0' " *ir*i% ele*%ri*
si!&l; $&' s*e!a $e !ai D)s. Se
ali!e"%ea0' *ir*i%l la srsa re(labil' $e *re"% *)"%i";
A
la 2 :. Se !'s)ar' val)rile %e"si"ii la *a&e%ele &)+i"ii $e *i*i% A6 #i i"%e"si%'+ii *re"%li ele*%ri* &ri" &)r+i"ea res&e*%iv' a&)i se %re* val)rile /" %abel. Se *re#%e val)area
V
?
%e"si"ii $e ali!e"%are a *ir*i%li * aD%)rl b%)"li &)%e"+i)!e%ri* al srsei $e ali!e"%are #i se !'s)ar' $i" ") val)rile i"%e"si%'+ii
A E 9r
Nr d!t @ ?
1
#i %e"si"ii la *a&e%ele &)r+i"ii.
Re0l%a%ele !'sr'%)ril)r se %re* /" %abel. 2
5
4
,
=
%erinţe"
'+ ()
'7
a7 Reali0a+i ex&eri!e"%l $es*ris !ai ss #i
*al*la+i re0is%e"+a ele*%ri*' a &)r+i"ii A6? b7 Trasa+i (rafi*l @= f#?$?
= : + (A)
7
79+<
79<
79<
37
'
IV.:. Stu*iu# *epen*en-ei re;i%ten-ei e#ectrice ! unui con*uctor *e #ungime9 %ec-iune $i re;i%ti(it!te e#ectric
$ateriale necesare &la*a * *)"$*%)are $e *r)!-"i*el #i !a"(a"i"'; $e $iferi%e l"(i!i #i se*+i"i; )!e%r; *)"$*%)are ele*%ri*e $e le('%r' * fi#' ba"a"'. $od de lucru Se se%ea0' !l%i!e%rl as%fel /"*@% s' !'s)are re0is%e"+a ele*%ri*'. Se
!'s)ar' re0is%e"+a ele*%ri*' a "i fir $e *r)!-"i*el; $e l"(i!e 9;5 !. #i $ia!e%r 9; !!.; a&)i se ")%ea0' val)area /" %abel. Se &r)*e$ea0' la fel * " fir $e *r)!"i*el $e l"(i!e 1!. #i se*+i"e 9; !!; a&)i * " fir $e *r)!-"i*el $e l"(i!e 9;5 ! #i se*+i"e 9; !!.; iar /" fi"al * " fir $e !a"(a"i"' $e l"(i!e 9;5!. #i se*+i"e 9; !!.
Cr)!-"i*el
Cr)!-"i*el
Cr)!-"i*el
Ma"(a"i"a
<1 199 19-8 !
<1 199 19-8 !
<1 199 19-8 !
<2 19-8 !
l 9;5 ! Y 9; !!
l 1 ! Y 9; !!
l 9;5 ! Y 9; !!
l 9;5 ! Y 9; !!
#A$ -
%erinţe" C)!&ara+i val)rile )b+i"%e #i r's&"$e+i la /"%reb'ri C! $e&i"$e R $e l"(i!ea *)"$*%)rliF
................................................................................................................................................ -
C! $e&"$e R $e aria se*+i"ii *)"$*%)rliF ................................................................................................................................................
-
C! $e&i"$e R $e re0is%ivi%a%ea ele*%ri*'F ................................................................................................................................................
"*'l0i+i "l $i"%re *)"$*%)ri; !'sra+i-i re0is%e"+a #i *)!&ara+i-) * val)area a"%eri)ar' /"*'l0irii. Ce *)"s%a%a+iF -
................................................................................................................................................ 38
IV.<. Grup!re! re;i%tori#or 1 &r
Scopul lucrării 3e%er!i"area; &e *ale %e)re%i*' #i &e *ale ex&eri!e"%al'; a re0is%e"+ei ec*i/a!ente a unei rup%ri de doi re$itori !eai în erie"
$ateriale necesare" *ase%e * re0is%)ri ; R1
R2
*)"$*%)are $e le('%r'; )!e%r? $od de lucru" Le(a+i $)i re0is%)ri; * re0is%e"+e *")s*%e; /" serie a&)i !'sra+i re0is%e"+a e*ivale"%' a (r&'rii; f)l)si"$ )!e%rl #i %re*e+i val)area !'sra%' /" %abell $e !ai D)s. H)l)si"$ rela+ia !a%e!a%i*' a re0is%e"+ei e*ivale"%e a "ei (r&'ri serie $e $)i re0is%)ri; *al*la+i re0is%e"+a e*ivale"%' a (r&'rii #i *)!&ara+i-) * val)area )b+i"%' &ri"
!'srare................................................................................................................................... R ' /
R+/
R %erie?m%ur!t/
R %erie?c!#cu#!t/
-
Ce )bserva+iF..............................................................................................................................
-
3e "$e ar fi &%% a&'rea eve"%alele er)riF ............................................................................
2 &r
R1
%erinţă" Re&e%a+i &r)*e$ra $e !ai ss le(@"$ re0is%)rii /" &aralel.Cal*la+i re0is%e"+a e*ivale"%' a (r&'rii &aralel #i
*)!&ara+i-)
*
val)area
)b+i"%'
&ri"
!'srare.
........................................................................................................ R2
R ' /
R+/
R p!r!#e#?m%ur!t/
R p!r!#e#?c!#cu#!t/
3 &r
%erinţă" Reali0a+i ) (r&are !ix%' $i" %rei re0is%)ri; rela+i &r)*e$ra $e !ai ss #i *al*la+i re0is%e"+a e*ivale"%' a (r&'rii *)!&ar@"$-) * val)area )b+i"%' &ri" !'srare. 3ese"a+i s*e!a &e *aie%. 39
IV.=. Verific!re! #egii I ! #ui irc,,off
Scopul lucrării" :erifi*area ex&eri!e"%al' a le(ii I a li >ir*)ff? #eoria lucrării" S!a i"%e"si%'+il)r *re"+il)r *are i"%r' /"%r-" ")$ es%e e(al' * s!a i"%e"si%'+il)r *re"+il)r *are ies $i" ")$. $ateriale necesare" srs' $e D)as' %e"si"e; s&)r%ri * be*ri; a!&er!e%re; *)"$*%)are ele*%ri*e $e le('%r' * fi#' ba"a"'? $od de lucru" Reali0a+i ) re+ea ele*%ri*'; $&' s*e!a $a%'. Ali!e"%a+i re+eaa la srsa
re(labil' $e *re"% *)"%i"; la 2 :. M'sra+i val)rile i"%e"si%'+ile *re"+il)r ele*%ri*i *e &ar*r( fie*are la%r' /" &ar%e a&)i %re*e+i val)rile /" %abel. Cre#%e+i val)area %e"si"ii $e ali!e"%are a re+elei * aD%)rl b%)"li &)%e"+i)!e%ri* al srsei $e ali!e"%are #i re&e%a+i &r)*e$ra. A1
I
I1
2
A1 I3 A1
E ,r
Nr d!t
1
2
5
? 1 #A$ ? 2 #A$ ? 3 #A$ ? 2 D ? 3 #A$
%erinţă" C)!&ara+i; &e"%r fie*are $e%er!i"are /" &ar%e; ? 1 * ? 2 D ? 3. Ce )bserva+iF
.................................................................................................................................................... 'valuarea elevilor"
N!ele elevliG (r&ei
Reali0area !)"%aDli 5 &"*%e7
Ci%irea *)re*%' a $a%el)r 2 &"*%e7
Reali0area *al*lel)r 2 &"*%e7
T)%al &"*%aD 119 &.7
40
IV.. Determin!re! puterii unui &ec
Scopul experimentului $e%er!i"area &%erii "i be*? #eoria lucrării E"er(ia ele*%ri*' es%e e"er(ia re*e&+i)"a%' $e " *)"s!a%)r $e la ) srs'; &ri" i"%er!e$il *@!&li ele*%ri*;. Ea es%e ) e"er(ie re*e&+i)"a%' #i i!e$ia%
*)"s!a%'. E = @ ? Δt ; "$e U es%e %e"si"ea la *a&e%ele *)"s!a%)rli; I es%e i"%e"si%%ea *re"%li ele*%ri* *e s%raba%e *)"s!a%)rl iar
% es%e i"%ervall $e %i!& *@% *)"s!a%)rl
es%e &ar*rs $e *re"% ele*%ri*. E"er(ia ele*%ri*' $e0v)l%a%' /" "i%a%ea $e %i!& la b)r"ele "i *)"s!a%)r se "!e#%e &%ere ele*%ri*'. = ∆ =
∙ ∙∆
∆
∙9[]=( )
$ateriale necesare srs' $e D)as' %e"si"e; a!&er!e%r; v)l%!e%r; be* * i"*a"$es*e"+'- 4 :; s&)r% &e"%r be*; *)"$*%)are ele*%ri*e $e le('%r' * fi#' ba"a"'. $od de lucru Se reali0ea0' " *ir*i% ele*%ri* $&' s*e!a $e !ai D)s. Se ali!e"%ea0'
*ir*i%l la srsa re(labil' $e *re"% *)"%i"; !ai /"%@i la 2 :. Se
6!c
>
A
!'s)ar' val)rile
%e"si"ii la *a&e%ele be*li #i
*re"%li ele*%ri* &ri" be*; a&)i se %re* val)rile /"
%abel. Se
)bserv' !)$l /" *are l!i"ea0' be*l #i se ")%ea0' *)"s%a%area f'*%' /" %abel; la rbri*a )bserva+ii. Se re&e%' &r)*e$ra; !'ri"$
V
?
i"%e"si%'+ii
&+i" *@%e &+i" %e"si"ea $e ali!e"%are * aD%)rl A E 9r
b%)"li
&)%e"+i)!e%ri* al srsei :; 4:; 8:7. Re0l%a%ele !'sr'%)ril)r se ")%ea0' /" %abel. T)% /" %abel se ")%ea0' #i val)rile ")!i"ale ale
&%erii #i %e"si"ii be*li; &e *are le ('si! i"s*ri&+i)"a%e &e be*. !nsin! nminal7
V/
t!r ! nminal7
/
.7rimi m7srat! @ ? V/ A/
.7rimi calclat! = @ ? /
%6s!rFaGii #as
/
%erinţe" a7. Reali0a+i ex&eri!e"%l $e !ai ss #i *al*la+i &%erea *)"s!a%' $e be*? b7 C)!&ara+i; &e"%r fie*are se% $e $a%e /" &ar%e; &%erea ")!i"al' a be*li * &%erea
*)"s!a%' #i *)rela+i $a%ele * )bserva+iile ")%a%e. 'valuarea activităţii elevilor 7ealizarea 8nre!istrarea 'fectuarea 'fectuarea 6umele elevului0!rupei montaului datelor calculelor observatiilor 9 + punct: 9* puncte: 9* puncte: 9* puncte:
%orelarea intre date şi obs. 9* puncte:
41
IV.. Stu*iu# tr!n%form!toru#ui
Scopul experimentului es%e $e a ils%ra &r)&rie%'+ile "i %ra"sf)r!a%)r ele*%ri*? #eoria lucrării Tra"sf)r!a%)rl es%e " a&ara% s%a%i* ba0a% &e fe")!e"l $e i"$*+ie
ele*%r)!a("e%i*'. El &ri!e#%e &%ere ele*%ri*'; /" *re"% al%er"a%iv; la ) %e"si"e U 1 #i ) i"%e"si%a%e I1 a&li*a%' "i *ir*i% "!i% &ri!ar #i ) re$'; * a*eea#i fre*ve"+'; la ) %e"si"e U2 #i ) i"%e"si%a%e I 2; la b)r"ele "i *ir*i% "!i% se*"$ar. E al*'%i% $i"%r-" *a$r $e fier; *are re&re0i"%' *ir*i%l !a("e%i* /"*is; &e *are se b)bi"e0' $)' /"f'#r'ri b)bi"e7 $i" s@r!' $e *&r. R)ll *a$rli $e fier es%e $e a reali0a *&laDl !a("e%i* /"%re *ele $)' /"f'#r'ri; &ri" *)"*e"%rarea
li"iil)r
*@!&li
!a("e%i* #i $e a !'ri flxl !a("e%i* &ri" s&irele *el)r $)' *ir*i%e. Cir*i%l se*"$ar es%e (e"era%)rl $e %e"si"e /" li"ia $e /"%rebi"+are. S' &res&"e! *' *ir*i%l &ri!ar are ) /"f'#rare * N1 s&ire iar se*"$arl N 2; iar %ra"sf)r!a%)rl f"*+i)"ea0' /" ()l i 29; *ir*i%l se*"$ar " are *)"s!!a%)r7. 3a*' se a&li*' %ra"sf)r!a%)rli %e"si"ea al%er"a%iv' 1 $e val)are efe*%iv' U 17; /" &ri!ar a&are *re"%l $e i"%e"si%a%e i 1 $e val)are efe*%iv' I17; *are $' "a#%ere flxli !a("e%i* al%er"a%iv * val)area i"s%a"%a"ee f f! *)s
(%. A*es% flx variabil; *are s%raba%e a!bele /"f'#r'ri; fa*e s' a&ar'; /" *ele N 1 s&ire ale &ri!arli ) %e"si"e $e a%)i"$*+ie e1; iar /" se*"$ar ) %e"si"e e 2. ∆ =
∆
9
= = ∆
=
Pri" /!&'r+ireL
=
∆
3ar /" &ri!ar 1 !1 1 ? 1 "$e R 1 es%e re0is%e"+a &ri!arli. 3a*' val)area ei
es%e !i*a; a%"*i !1ZH 1 .Se!"l !i"s ara%' *' %.e.!. $e a%)i"$*+ie es%e /" )&)0i+ie $e fa0' * %e"si"ea re+elei $e ali!e"%area %ra"sf)r!%)rli; 1 " a
uncionarea în o!-
!2 = 2
=
" val)ri abs)l%e;
≈
=
= = ra&)r% $e %ra"sf)r!are
$ateriale necesare b)bi"' * 99 s&ire; b)bi"' * 1499 s&ire; srs' $e D)as' %e"si"e $e *re"% al%er"a%iv; !l%i!e%r; *)"$*%)are $e le('%' * fi#e $e %i& ba"a"'. $od de lucru C!;u# '. Stu*iu# tr!n%form!toru#ui ri*ictor *e ten%iune. Se &" b)bi"ele &e !e0l $e
fier. Cir*i%l &ri!ar * b)bi"a $e 99 s&ire7 se ali!e"%ea0' la srsa $e *re"% al%er"a%iv; iar 42
/" se*"$ar * b)bi"a $e 1499 s&ire7 le('! !l%i!e%r &e"%r a !'sra %e"si"ea. :arie! %e"si"ea $i" &ri!ar #i *i%i! %e"si"ea /" se*"$ar &e"%r fie*are val)are a %e"si"ii $i" &ri!ar. C a*ela#i !l%i!e%r &%e! !'sra #i %e"si"ea $i" &ri!ar. Tre*e! $a%ele /" %abel.
Nr :!t
@ 1
@ 2
V/
V/
=
I =
1 2 3 4 ) C!;u# +. Stu*iu# tr!n%form!toru#ui co&ortor *e ten%iune
P"e! b)bi"ele &e !e0l $e fier. Cir*i%l &ri!ar * b)bi"a $e 1499 s&ire7 se ali!e"%ea0' la srsa $e *re"% al%er"a%iv; iar /" se*"$ar * b)bi"a $e 99 $e s&ire7 le('! !l%i!e%r &e"%r a !'sra %e"si"ea. :arie! %e"si"ea $i" &ri!ar #i *i%i! %e"si"ea /" se*"$ar &e"%r fie*are val)are a %e"si"ii $i" &ri!ar. C a*ela#i !l%i!e%r &%e! !'sra #i %e"si"ea $i" &ri!ar. Tre*e! $a%ele /" %abel. Nr :!t
@ 1
@ 2
V/
V/
=
I =
1 2 3 4 )
%erinţe a7. Reali0a+i ex&eri!e"%ele $e !ai ss #i *)!&le%a+i %abelele? b7. C)!&ara+i *ele
$)' %ra"sf)r!a%)are................................................................................................................ .................................................................................................................................................... 43
IV.6. Efecte#e curentu#ui e#ectric 1 5f!ctl cimic al cr!ntli !l!ctric,
Scopul lucrarii" P"erea /" evi$e"+' a efe*%li *i!i* al *re"%li ele*%ri*? $ateriale necesare" vas $e ele*%r)li0'; fire $e le('%r'; srs' $e %e"si"e; a&' $is%ila%'; CSO; s&a%l'; ba(e%'? $od de lucru" -
U!&le+i vasl $e ele*%r)li0' * a&' $is%ila%'
a&)i &"e+i 2 li"(ri+e $e CSO.; f)l)si"$ s&a%la . A!es%e*a+i * ba(e%a &@"' se $i0)lv'? -
Reali0a+i !)"%aDl $i" fi(r'; le(@"$ vasl $e
ele*%r)li0'; &rev'0% * 2 ele*%r)0i $e (rafi%; /" serie * " a!&er!e%r #i ) srs' $e %e"si"e? -
Ali!e"%a+i *ir*i%l la srsa $e %e"si"e. %erinţe"
-
-
S*rie+i e*a+ia $e $is)*iere a slfa%li $e *&r ..................................................................... Ur!ari+i *ei $)i ele*%r)0i %i!& $e *@%eva !i"%e #i s*rie+i *e )bserva+i la ele*%r)$l
&)0i%iv ........................................................................................................................................ -
"%rer&e+i ali!e"%area *ir*i%li; s*)a%e+i *a&a*l vasli #i s*rie+i *e )bserva+i la
ele*%r)$l "e(a%iv ....................................................................................................................................................... ...................................................................................................................................................... - Ex&li*a+i fe")!e"l &e%re*% ....................................................................................................................................................... ...................................................................................................................................................... ;7'U%-
Ce %e"si"e (e"erea0'F .............................................................................................................
44
2 5f!ctl magn!tic al cr!ntli !l!ctric,
Scopul lucrării" P"erea /" evi$e"+' a efe*%li !a("e%i* al *re"%li ele*%ri*?
$ateriale necesare s&&)r% "iversal * *le!e; *a$re * *)"$*%)are; $e $iferi%e f)r!e;
*)"$*%)are $e le('%r'; srs' $e %e"si"e; &ili%r' $e fier; a* !a("e%i*; ba(e%' $e s%i*l'? $od de lucru" C srsa $e %e"si"e )&ri%'; *)"e*%a+i *ablrile $e le('%r' la *a$rl $e &e s&)r%l $e &las%i*; /!&ra#%ia+i &ili%r' $e fier &e s&)r% si a#e0a+i /" !iDl)*l a*es%ia " a* !a("e%i*. Ali!e"%a+i *a$rl la srsa #i *i)*a"i+i s)r &e s&)r% * ba(e%a $e s%i*l'.
Ceri"+e -
S*rie+i *e a+i )bserva%
...................................................................................................................................................... -
S*i!ba+i se"sl *re"%li &ri" *)"$*%)r. Ce se /"%@!&l' * a*l !a("e%i*F
....................................................................................................................................................... -
Ex&li*a+i fe")!e"l &e%re*%
...................................................................................................................................................... ....................................................................................................................................................... ;7'U%-
!ie0 $e fier; 2 *)"$*%)are $e le(a%ra si srsa $e ali!e"%are C! &r)*e$a+iF .................................................................................................................................................... 45
IV.'7. Inter!c-iune! ! *ou con*ucto!re p!r!#e#e p!rcur%e *e curent e#ectric continuu
Scopul lucrării" P"erea /" evi$e"+' a f)r+ei $e i"%era*+i"e ele*%r)!a("e%i*' $i"%re $)' *)"$*%)are &ar*rse $e *re"+i ele*%ri*i s%a+i)"ari.
+
_
C" "
C" ."
7ina&o&etru
Cadru &obi! Cadru
A
$ateriale necesare" srs' $e *.*.; 2 *a$re * *)"$*%)are ; s&)r% &e"%r *a$re; *)"$*%)are $e le('%r'; $i"a!)!e%r; a!&er!e%r. $od de lucru" Reali0a+i !)"%aDl ele*%ri*;
f)l)si"$ $)' *a$re * *)"$*%)are; !)bile; *are se asa0'; /" abse"+a *re"%li; /" &la"ri &aralele. C)"$*%)rl $e D)s se s&iDi"a &e " s&)r%; as%fel /"*@% s' r'!@"' fix; iar *el $e ss; !)bil; se lea(' * " fir $e " $i"a!)!e%r se"sibil. %erinţe"- A&li*a+i ) %e"si"e *a$rel)r; as%fel /"*@% ele s' fie &ar*rse $e *re"+i ele*%ri*i * a*ela#i se"s. Observa+i *e se i"%@!&l'; *i%i+i i"$i*a+ia $i"a!)!e%rli si ")%a+i ........................................................................................... -
S*i!ba+i se"sl *re"%li /"%r-"l $i" *)"$*%)are ; as%fel /"*@% se"sl *re"+il)r &ri"
*)"$*%)are s' fie )&s. Observa+i *e se /"%@!&l' ; *i%i+i i"$i*a+ia $i"a!)!e%rli #i ")%a+i .......................................................................................................................................... -
M'ri+i i"%e"si%a%ea *re"%li &ri" *)"$*%)are; )bserva+i *e se /"%@!&l'; *i%i+i i"$i*a+ia
$i"a!)!e%rli #i ")%a+i.............................................................................................................. -
M'ri+i $is%a"+a $i"%re *)"$*%)are; )bserva%i *e se /"%a!&l'; *i%i%i i"$i*a+ia $i"a!)!e%rli
si ")%a+i ...................................................................................................................................... -
C)"*l0ii...................................................................................................................................
46
