Essential University Physics, 3e (Wolfson) 3e (Wolfson) Chapter 34 Particles and Waves Waves
3 4. 1 Co nc e pt ua lQue s t i o ns 1) Monochromatic light strikes a metal surface and electrons are ejected from the metal. If the intensity of the light is increased, what will happen to the ejection rate and maximum energy of the electrons? A) greater ejection rate same maximum energy !) same ejection rate greater maximum energy ") greater ejection rate greater maximum energy #) same ejection rate same maximum energy Answer$ A %ar$ 1
&) A 'eam of red light and a 'eam of (iolet light each deli(er d eli(er the same power on a surface. or which 'eam is the num'er of o f photons hitting the surface per second the greatest? A) the red 'eam !) the (iolet 'eam ") It is the same for 'oth 'eams. Answer$ A %ar$ 1
*) At a'solute temperature T , a 'lack 'ody radiates its peak intensity at wa(elength + . At a'solute temperature & &T T , what would 'e the wa(elength of the peak intensity? A) 1+ !) &+ ") + #) +-& ) +-1 Answer$ # %ar$ 1
/) A nonrelati(istic electron and a nonrelati(istic proton ha(e the same de !roglie wa(elength. 0hich of the following statements a'out these particles are accurate? 2here may 'e more than one correct choice.) A) !oth particles ha(e the same speed. !) !oth particles ha(e the same kinetic energy. ") !oth particles ha(e the same momentum. #) 2he electron has more kinetic energy than the proton. ) 2he electron has more momentum than the proton. Answer$ ", # %ar$ 1
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6) If the accuracy in measuring the position of a particle increases, the accuracy in measuring its (elocity will A) increase. !) decrease. ") remain the same. #) It is impossi'le to say since the two measurements are independent and do not affect each other. Answer$ ! %ar$ 1
) If the accuracy in measuring the (elocity of a particle increases, the accuracy in measuring its position will A) increase. !) decrease. ") remain the same. #) It is impossi'le to say since the two measurements are independent and do not affect each other. Answer$ ! %ar$ 1
3 4 . 2 Pr o bl e ms 1) 7ight of wa(elength /44 nm falls on a metal surface ha(ing a work function 1.84 e%. 0hat is the maximum kinetic energy of the photoelectrons emitted from the metal? c 9 *.44 : 14; m-s, h 9 .& : 14<*/ = > s 9 /.1/1 : 14<16 e( > s, 1 e% 9 1.4 : 14<1 =) A) /.6& e% !) *.11 e% ") 1./1 e% #) &.;& e% ) 1.84 e% Answer$ " %ar$ 1
&) 0hen a certain metal is illuminated 'y light, photoelectrons are o'ser(ed pro(ided that the wa(elength of the light is less than nm. 0hich one of the following (alues is closest to the work function of this metal? h 9 .& : 14<*/ = > s, c 9 *.44 : 14; m-s, 1 e% 9 1.4 : 14<1 =) A) 1. e% !) &.4 e% ") &.& e% #) &.* e% Answer$ A %ar$ 64@
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*) pon 'eing struck 'y &/4
s, c 9 *.44 : 14; m-s, 1 e% 9 1.4 : 14<1 =) A) *.8* e% !) *.1* e% ") /.** e% #) /.& e% Answer$ A %ar$ 64@
/) In a photoelectric effect experiment, electrons emerge from a copper surface with a maximum kinetic energy of 1.14 e% when light shines on the surface. 2he work function of copper is /.6 e%. 0hich one of the following (alues is closest to the wa(elength of the light? h 9 .& : 14< */ = > s, c 9 *.44 : 14; m-s, 1 e% 9 1.4 : 14<1 =) A) &&4 nm !) 164 nm ") *4 nm #) 1144 nm Answer$ A %ar$ &8
6) A metal ha(ing a work function of &.6 e% is illuminated with white light that has a continuous wa(elength 'and from /44 nm to 844 nm. or which one of the following ranges of the wa(elength 'and in this white light are photoelectrons BC2 produced? h 9 .& : 14<*/ = > s, c 9 *.44 : 14; m-s, 1 e% 9 1.4 : 14 <1 =) A) 644 nm to 844 nm !) /44 nm to 64 nm ") 644 nm to 64 nm #) /44 nm to 644 nm ) 64 nm to 844 nm Answer$ A %ar$ 14
) A metal ha(ing a work function of &./ e% is illuminated with monochromatic light whose photon energy is /.4 e%. 0hat is the maximum kinetic energy of the photoelectrons produced 'y this light? h 9 .& : 14<*/ = > s, 1 e% 9 1.4 : 14<1 =) A) &. : 14<1 = !) *.; : 14<1 = ") /.8 : 14<1 = #) 6.6 : 14<1 = ) ./ : 14<1 = Answer$ A %ar$ 64@
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8) A metal ha(ing a work function of &.; e% is illuminated with monochromatic light whose photon energy is *. e%. 0hat is the threshold freDuency for photoelectron production? h 9 .& : 14<*/ = > s, 1 e% 9 1.4 : 14<1 =) A) .; : 141/ EF !) &.8 : 141/ EF ") 8. : 141/ EF #) ;.6 : 141/ EF ) ./ : 141/ EF Answer$ A %ar$ 64@
;) A stopping potential of 4.64 % is reDuired when a phototu'e is illuminated with monochromatic light of wa(elength 64 nm. Monochromatic light of a different wa(elength is now shown on the tu'e, and the stopping potential is measured to 'e &.*4 %. 0hat is the wa(elength of this new light? c 9 *.44 : 14; m-s, e 9 < 1.4 : 14<1 ", h 9 .& : 14<*/ = > s, 1 e% 9 1.4 : 14<1 =) A) *&4 nm !) *44 nm ") */4 nm #) *4 nm ) /14 nm Answer$ A %ar$ 64@
) A metal surface has a work function of 1.64 e%. "alculate the maximum kinetic energy, in e%, of electrons ejected from this surface 'y electromagnetic radiation of wa(elength *11 nm. c 9 *.44 : 14; m-s, h 9 .& : 14<*/ = > s, e 9 < 1.4 : 14<1 ", 1 e% 9 1.4 : 14<1 =) Answer$ &.64 e% %ar$ 64@
14) 0hen a metal surface is illuminated with light of wa(elength /* 8 nm, the stopping potential for photoelectrons is 1.8 %. c 9 *.44 : 14; m-s, h 9 .& : 14<*/ = > s, e 9 < 1.4 : 14<1 ", 1 e% 9 1.4 : 14<1 =, mel 9 .11 : 14<*1 kg) a) 0hat is the work function of the metal, in e%? ') 0hat is the maximum speed of the ejected electrons? Answer$ a) 1.18 e% ') 8. : 146 m-s %ar$ 1
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11) Gamma rays are photons with (ery high energy. Eow many (isi'le s, c 9 *.44 : 14; m-s) A) 1.4 : 14 !) 1./ : 14; ") .& : 14 #) *. : 14* Answer$ A %ar$ 64@
1&) An ;/ s) A) 1.* × !) &. × ") .* × #) 1./ × Answer$ A %ar$ 64@
1*) A light 'eam from a &.1 s, c 9 *.44 : 14; m-s) A) .8 : 1416 !) ;.; : 1416 ") 1.1 : 141 #) 1.* : 141 Answer$ A %ar$ 64@
1/) A laser emits light of wa(elength /* nm during a 'rief pulse that lasts for &6 ms and h as a total energy of 1.& =. Eow many photons are emitted in that single pulse? c 9 *.44 : 14; m-s, h 9 .& : 14<*/ = > s) A) &.; : 141; !) . : 141 ") *./ : 141 #) 1.1 : 1418 ) &.& : 1418 Answer$ A %ar$ 64@
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16) A photon of initial wa(elength 4.61 nm, after 'eing scattered from a free electron at rest, mo(es off at an angle of 1&4G with respect to its incident direction. mel 9 .11 : 14<*1 kg, h 9 .& : 14<*/ = > s, c 9 *.44 : 14; m-s) a) 0hat is the wa(elength of the scattered photon? ') 0hat is the energy of the scattered photon? Answer$ a) 4.66 nm ') *.4/ : 14<1 = %ar$ 1
1) In a particular case of "ompton scattering, a photon collides with a free electron and scatters 'ackwards. 2he wa(elength after the collision is exactly dou'le the wa(elength 'efore the collision. 0hat is the wa(elength of the incident photon? mel 9 .11 : 14<*1 kg, h 9 .& : 14< */ = > s, c 9 *.44 : 14; m-s) A) *. pm !) /.; pm ") &./ pm #) 1.& pm ) .4 pm Answer$ ! %ar$ 1
18) A 'eam of x s, c 9 *.44 : 14; m-s) A) 4.186 pm !) 4.&8 pm ") 4.444 pm #) 4.*6 pm ) 4.814 pm Answer$ %ar$ 1
1;) A photon of wa(elength & pm is scattered 'y a stationary electron. 0hat is the maximum possi'le energy loss of the photon? mel 9 .11 : 14<*1 kg, h 9 .& : 14<*/ = > s, c 9 *.44 : 14; m-s) A) /.4 ke% !) 8.4 ke% ") 14 ke% #) .1 ke% ) 1& ke% Answer$ # %ar$ 1
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1) A photon of wa(elength 1;.4 pm is scattered through an angle of 1&4G 'y a stationary electron. 0hat is the wa(elength of the scattered photon? mel 9 .11 : 14<*1 kg, h 9 .& : 14<*/ = > s, c 9 *.44 : 14; m-s) A) 1.& pm !) &4./ pm ") &1. pm #) &&. pm ) &/.1 pm Answer$ " %ar$ 1
&4) H s, c 9 *.44 : 14; m-s, 1 e% 9 1.4 : 14<1 =) Answer$ &. : 14/ e% %ar$ 1
&1) 2he !ohr radius of the hydrogen atom is 4.6& : 14<14 m. 0hat is the radius of the n 9 & state? A) 1.4 : 14<14 m !) &.1& : 14<14 m ") 4.&6 : 14<14 m #) 4.6& : 14<14 m ) /.&* : 14<14 m Answer$ ! %ar$ 1
&&) 2he energy of the ground state in the !ohr model of the hydrogen atom is <1*. e%. 2he energy of the n 9 & state of hydrogen in this model is closest to A) <*./ e%. !) <.; e%. ") <1.8 e%. #) <1*. e%. )
&*) 2he energy of the ground state in the !ohr model of the hydrogen atom is <1*. e%. In a transition from the n 9 & state to the n 9 / state, a photon of energy A) *./4 e% is emitted. !) *./4 e% is a'sor'ed. ") &.66 e% is emitted. #) &.66 e% is a'sor'ed. ) 4.;6 e% is a'sor'ed. Answer$ # %ar$ 1 8 "opyright 3 &41 5earson ducation, Inc.
&/) 0hat is the freDuency of the light emitted 'y atomic hydrogen with m 9 ; and n 9 1&? 2he yd'erg constant is R 9 1.48 : 148 m<1, c 9 *.44 : 14; m-s) A) &.; : 141* EF !) 1./* : 141* EF ") 8./ : 141* EF #) ;.;& : 141* EF ) 1.46 : 141* EF Answer$ A %ar$ 1
&6) 0hat is the or'ital radius of the
excited state in the !ohr model of the hydrogen atom? 2he ground
&) 7ight excites atomic hydrogen from its lowest le(el to the n 9 / le(el. 0hat is the energy of the light? 2he energy of the lowest le(el is <1*. e%. A) 1&.; e% !) *./4 e% ") 4.;64 e% #) &./ e% Answer$ A %ar$ 1
&8) 7ight shines through atomic hydrogen gas. It is seen that the gas a'sor's light readily at a wa(elength of 1.* nm. 0hat is the (alue of n of the le(el to which the hydrogen is 'eing excited 'y the a'sorption of light of this wa(elength? Assume that the most of the atoms in the gas are in the lowest le(el. h 9 .& : 14<*/ = > s, c 9 *.44 : 14; m-s, 1 e% 9 1.4 : 14 <1 =, the yd'erg constant is R 9 1.48 : 148 m<1) A) 1/ !) 1 ") 11 #) &1 Answer$ A %ar$ 1
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&;) A hydrogen atom is in its n 9 & excited state when its electron a'sor's a photon of energy . 0hat is the energy of the resulting free electron? 2he lowest le(el energy state of hydrogen is <1*. e%. h 9 .& : 14<*/ = > s, 1 e% 9 1.4 : 14<1 =) A) 6.1 e% !) . e% ") . e% #) 8.8 e% Answer$ A %ar$ 64
&) A hydrogen atom initially in the n 9 state decays to the n 9 & state. 2he emitted photon is detected in a photographic plate. 0hat is the wa(elength of the detected photon? 2he lowest le(el energy state of hydrogen is <1*. e%. h 9 .& : 14<*/ = > s, 1 e% 9 1.4 : 14 <1 =, c 9 *.44 : 14; m-s) A) /14 nm !) *.; nm ") 144 nm #) *.1 nm Answer$ A %ar$ //
*4) A hydrogen atom is excited to the n 9 14 stated. It then decays to the n 9 / state 'y emitting a photon which is detected in a photographic plate. 0hat is the freDuency of the detected photon? 2he lowest le(el energy state of hydrogen is <1*. e%. h 9 .& : 14<*/ = > s, 1 e% 9 1.4 : 14 < 1 =) A) *./ : 141/ EF !) 4.;6 : 141/ EF ") 1.&8 : 141/ EF #) /.46 : 141/ EF ) 1.8* : 141/ EF Answer$ %ar$ 1
*1) A hydrogen atom makes a downward transition from the state to the n 9 6 state. ind the wa(elength of the emitted photon. 2he lowest le(el energy state of hydrogen is <1*. e%. h 9 .& : 14<*/ = > s, 1 e% 9 1.4 : 14 <1 =, c 9 *.44 : 14; m-s) A) &./* Jm !) 1./ Jm ") 1./ Jm #) &.& Jm Answer$ A %ar$ 16
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*&) Kuppose that in a parallel uni(erse, the proton and electron were identical to their counterparts in our own uni(erse H"52 that the electron had twice as much charge as our electron. In our present uni(erse, the radius o f the first !ohr or'it for hydrogen is a4 and the speed of an electron in that or'it is v4. In the parallel uni(erse a) what would 'e the radius in terms of a4) of the first !ohr or'it for hydrogen? ') what would 'e the speed in terms of v4) of an electron in the first !ohr or'it for h ydrogen? Answer$ a) a4-& ') &v4 %ar$ 1
**) In the (icinity of what freDuency does an o'ject with a temperature of 1444 L radiate the largest amount of power? c 9 *.44 : 14; m-s, 0ien displacement law constant eDuals &.4 : 14< * m > L, σ 9 6.84 : 14<; 0-m& > L /) A) 1.4 : 141/ EF !) ;.4 : 141/ EF ") &.* : 141/ EF #) .8 : 141/ EF ) /.1 : 141/ EF Answer$ A %ar$ 1
*/) 0hat is the wa(elength of peak emission for a 'lack 'ody at *8G"? c 9 *.4 : 14; m-s, 0ien displacement law constant is &. : 14<* m > L, σ 9 6.8 : 14<; 0-m& > L /) A) / m !) ./ m ") & m #) 8.; m ) 8; m Answer$ ! %ar$ 1
*6) A perfectly 'lack 'ody at 144G" emits light of intensity I that has the strongest intensity near wa(elength λ. 2he temperature of this 'ody is now increased to &44G". a) In terms of I , what is the intensity at which this hotter 'od y radiates? ') In terms of λ, near what wa(elength does light radiated from this hotter 'ody ha(e the strongest intensity? Answer$ a) &. I ') 4.;4 λ %ar$ 1
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*) An electric current through a tungsten filament maintains its temperature at &;44 L. Assume the tungsten filament 'eha(es as an ideal radiator at that temperature. Bear what wa(elength does the filament emit the greatest power? σ 9 6.8 : 14<; 0-m& > L /, 0ien displacement law constant is &. : 14<* m > L) A) 1444 nm !) 1&44 nm ") 1/44 nm #) 144 nm ) 1;44 nm Answer$ A %ar$ 1
*8) An electric current through a tungsten filament maintains its temperature at &;44 L. Assume the tungsten filament 'eha(es as an ideal radiator at that temperature. If the radiating area o f the filament is &.4 : 14< m&, at what rate does it radiate energy? σ 9 6.84 : 14<; 0-m& > L /, 0ien displacement law constant is &.4 : 14<* m > L) A) 6.6 0 !) 8.4 0 ") ;.6 0 #) 14 0 ) 11.6 0 Answer$ ! %ar$ 1
*;) A perfectly 'lack sphere 1;.4 cm in diameter is held at a temperature of &16G". σ 9 6.84 : 14<; 0-m& > L /, 0ien displacement law constant is &.4 : 14<* m > L, h 9 .& : 14<*/ = > s, c 9 *.44 : 14; m-s) a) Bear what wa(elength does this sphere radiate most strongly? ') If all the radiated energy were at the wa(elength found in part a), how many photons would the sphere emit each second? Answer$ a) 6./ m ') .8 : 14&1 photons %ar$ 1
*) "alculate the kinetic energy in e%) of a nonrelati(istic neutron that has a de !roglie wa(elength of h 9 .& : 14<*/ = > s, mneutron 9 1.86 : 14<&8 kg, 1 e% 9 1.4 : 14<1 =) Answer$ ;./ e% %ar$ 64@
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/4) In a dou'le slit experiment, a 'eam of electrons strikes a pair of slits. 2he slits are 16 Jm apart, and the first interference maximum lies at an angle of 4.64 rad from the center of the interference pattern. 0hat is the momentum of the incoming electrons? h 9 .& : 14<*/ = > s, mel 9 .11 : 14<*1 kg) A) /./ : 14<&* kg > m-s !) &.& : 14<&* kg > m-s ") 1.1 : 14<&* kg > m-s #) . : 14<&* kg > m-s ) ;.; : 14<&* kg > m-s Answer$ %ar$ 1
/1) lectrons emerge from an electron gun with a speed of &.4 : 14 m-s and then pass through a pair of thin parallel slits. Interference fringes with a spacing of &.8 mm are detected on a screen far from the dou'le slit and fairly close to the center of the pattern. 0hat would the fringe spacing 'e if the electrons were replaced 'y neutrons with the same speed? mel 9 .11 : 14<*1 kg, mneutron 9 1.8 : 14<&8 kg) A) 1.6 m !) /. m ") 4.* nm #) 1.1 m ) 1.6 nm Answer$ A %ar$ 1
/&) 0hat is the energy of a photon that has a wa(elength eDual to the de !roglie wa(elength of a proton ha(ing a speed of 8.1 × m-s? m proton 9 1.8 : 14<&8 kg, c 9 *.44 : 14; m-s) A) &&4 ke% !) 164 ke% ") &4 ke% #) *4 ke% ) //4 ke% Answer$ A %ar$ 64@
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/*) Eow fast must a nonrelati(istic electron mo(e so its de !roglie wa(elength is the same as the wa(elength of a *./
//) A nonrelati(istic electron has a kinetic energy of 6./ e%. 0hat is the energy of a photon whose wa(elength is the same as the de !roglie wa(elength of the electron? mel 9 .11 : 14<*1 kg, c 9 *.44 : 14; m-s, 1 e% 9 1.4 : 14<1 =) A) &./ ke% !) &.& ke% ") &.4 ke% #) &.6 ke% ) &.8 ke% Answer$ A %ar$ 1
/6) A single slit is illuminated at normal incidence with a parallel 'eam of light ha(ing a wa(elength of 2he entire central 'and of the diffraction pattern is o'ser(ed at N4G. 2he illumination is now replaced 'y a nonrelati(istic 'eam of electrons, each ha(ing a kinetic energy of ;4 e%. 0hen this 'eam hits the slit at normal incidence, at what angle will the first minimum of the electron diffraction pattern occur? h 9 .& : 14<*/ = > s, mel 9 .11 : 14<*1 kg, 1 e% 9 1.4 : 14<1 =) A) 4.46 mrad !) 4.481 mrad ") 4.4/ mrad #) 4.1& mrad ) 4.1/ mrad Answer$ A %ar$ 64@
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/) 7ight of wa(elength 146 nm falls on a metal surface for which the work function is 6.44 e%. 0hat is the minimum de !roglie wa(elength of the photoelectrons emitted from this metal? h 9 .& : 14<*/ = > s 9 /.1/ : 14<16 e% > s, c 9 *.44 : 14; m-s, mel 9 .11 : 14<*1 kg, 1 e% 9 1.4 : 14<1 =) A) 4.&/ nm !) 4.** nm ") 4./8 nm #) 4. nm ) 4./ nm Answer$ " %ar$ 1
/8) A gas of helium atoms each of mass .6 : 14<&8 kg) are at room temperature of &4.4G". 0hat is the de !roglie wa(elength of the helium atoms that are mo(ing at the root s, the !oltFmann constant is 1.*; : 14 <&* =-L) A) 6.&& : 14<11 m !) 8.*; : 14<11 m ") 1.4/ : 14<14 m #) &.;& : 14<14 m ) *. : 14<14 m Answer$ ! %ar$ 1
/;) A nonrelati(istic electron is accelerated from rest through a potential difference. After acceleration the electron has a de !roglie wa(elength of ;;4 nm. 0hat is the potential difference though which this electron was accelerated? h 9 .& : 14<*/ = > s, e 9 < 1.4 : 14<1 ", mel 9 .11 : 14<*1 kg) A) 1. % !) 1.8 % ") &.& % #) &.6 % Answer$ A %ar$ 1
/) An electron inside a hydrogen atom is confined to within a space of 4.114 nm. 0hat is the minimum uncertainty in the electronOs (elocity? h 9 1.466 : 14<*/ = > s, mel 9 .11 : 14<*1 kg) A) 1.46 : 14 m-s !) 1.64 : 14 m-s ") 1.46 : 14; m-s #) 1.64 : 14; m-s ) 1.46 : 1414 m-s Answer$ A %ar$ *
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64) A measurement of an electronOs speed is &.4 : 14 m-s and has an uncertainty of 14P. 0hat is the minimum uncertainty in its position? h 9 1.466 : 14<*/ = > s, mel 9 .11 : 14<*1 kg) A) 4.& nm !) 4.6; nm ") 4.;8 nm #) 1.& nm ) 1. nm Answer$ ! %ar$ 1
61) A molecule of roughly spherical shape has a mass of .14 × 14<&6 kg and a diameter of 4.84 nm. 2he uncertainty in the measured position of the molecule is eDual to the molecular diameter. 0hat is the minimum uncertainty in the speed of this molecule? h 9 1.466 : 14<*/ = > s) A) 4.&6 m-s !) &.6 m-s ") &6 m-s #) 4.4&6 m-s ) 4.44&6 m-s Answer$ A %ar$ 1
6&) A nonrelati(istic electron is confined to a length of 6 44 pm on the x s, mel 9 .11 : 14<*1 kg, 1 e% 9 1.4 : 14<1 =) A) 4.4416 e% !) 4.416 e% ") 4.16 e% #) 1.6 e% ) 16 e% Answer$ " %ar$ 1
6*) A nonrelati(istic proton is confined to a length of & .4 pm on the x s, m proton 9 1.8 : 14<&8 kg) A) 4.6& e% !) 6.& e% ") 6& e% #) 6&4 e% ) 6&44 e% Answer$ ! %ar$ 1
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6/) A small dust particle of mass 8.4 × 14< g is 'eing o'ser(ed under a magnifying lens. Its position is determined to within 4.4464 mm. 1 y 9 *.16 : 148, h 9 1.466 : 14<*/ = > s) a) ind the minimum uncertainty in its (elocity implied 'y the uncertainty in its position. ') Assuming the dust particle is mo(ing at the speed you just found, how many years would it take for the particle to mo(e 1.4 mm? Answer$ a) &.8 : 14<&1 m-s ') 1.& : 1414 y %ar$ 1
66) 2he excited state of a certain atom is *.& e% N 4.&1 e%. h 9 1.466 : 14<*/ = > s 9 .61 : 14<1 e% > s, 1 e% 9 1.4 : 14 <1 =) a) 0hat is the a(erage lifetime of this state? ') If the excited energy were dou'led to ./ e% N 4.&1 e%, how would the lifetime 'e affected? Answer$ a) 1. fs ') unchanged since the uncertainty is still N4.&1 e% %ar$ 1
6) A certain particleOs energy is measured 'y a detector to within 1.4 : 14<1; =. 0hat is the minimum uncertainty we can ha(e in its arri(al time at the detector? h 9 1.466 : 14<*/ = > s) A) 1.1 : 14<16 !) 1.1 : 14<1/ ") 1.1 : 14<1* #) 1.1 : 14<1& ) 1.1 : 14<1 Answer$ %ar$ 1
68) 2he energy of an electron state has an uncertainty of 4.644 e%. 0hat is the minimum uncertainty in the lifetime of the le(el? h 9 1.466 : 14<*/ = > s 9 .61 : 14<1 e% > s, 1 e% 9 1.4 : 14<1 =) A) 1.*& : 14<16 !) ;.&; : 14<16 ") 1.*& : 14<11 #) ;.&; : 14<11 ) 1.*& : 14<; Answer$ A %ar$ 1
6;) 2he lifetime of an excited nuclear state is 1.4 ns. 0hat is the minimum uncertainty in the energy of this state? h 9 1.466 : 14<*/ = > s 9 .61 : 14<1 e% > s, 1 e% 9 1.4 : 14<1 =) A) 1.4 : 14< !) 1.4 : 14<&6 ") . : 14<&6 #) *.* : 14<8 ) . : 14<8 Answer$ %ar$ 1 1 "opyright 3 &41 5earson ducation, Inc.
6) A laser produces a 'eam of /444 s 9 .6 : 14<1 e% > s) A) & × 14< e% !) & × 14<6 e% ") & × 14
4) An ultra(iolet source produces a monochromatic 'eam of &44 s 9 .6 : 14<1 e% > s, c 9 *.44 : 14; m-s) A) 14< e% !) 14<6 e% ") 14
1) A //4 s 9 .6 : 14<1 e% > s) A) 6 × 14< s !) 6 × 14<8 s ") 6 × 14<; s #) 6 × 14< s ) 6 × 14<14 s Answer$ # %ar$ 1
&) An unsta'le particle produced in a high s 9 .6 : 14<1 e% > s) Answer$ 8.; : 14<&1 %ar$ 1
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