DATED : _______________________
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 1
DATED : _______________________
Name:_________________________________________ Class: _____________ Section:__________ Roll No: ________ Group:_______________________
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 2
DATED : _______________________
S. No
1 2 3 4 5 6 7 8
9 10 11 12 13 14
15 16
P. No
Date
To determine the unknown resistance by using a neon flash lamp and a capacitor. To convert the given galvanometer in to an ammeter up to the range [ 0 – 1 ] ampere. To convert the given galvanometer in to an voltmeter up to the range [ 0 – 1 ] volt. To calibrate a voltmeter by using a potentiometer. To calibrate an ammeter by using a potentiometer. To calibrate an ammeter and a voltmeter by using a potentiometer. To determine the low resistance of the given coil by Carey foster bridge. To determine the value of two unknown resistances by using a potentiometer and verify the law of combination of resistances in series or parallel. To determine the work function of a metal by using a sodium light. To determine the ionization potential of mercury. To set up half and full wave rectifier and study their waveforms on an oscilloscope. To study the characteristics of an RLC series acceptor circuit by plotting a response curve. To study the characteristics of an RLC rejecter circuit by plotting a response curve. To plot the characteristics curve of a semi conductor diode. Determine the forward and reverse impedances [Resistances]. To study the static characteristics of a given transistor in common emitter mode. To determine the Plank’s constant by using a spectrometer and hydrogen discharge tube.
ASIFJAH ZEHRAVI
Initial
01 05 10 15 18 21 25 31
36 40 44 52 57 62
65 70
CELL 0300 – 2568922 & 0341 – 6623062 3
DATED : _______________________
LIST OF EXPERIMENTS PRACTICAL [ III ] To determine the unknown resistance by using a neon flash lamp and a capacitor. To convert the given galvanometer in to an ammeter up to the range [ 0 – 1 ] ampere. To convert the given galvanometer in to an voltmeter up to the range [ 0 – 1 ] volt. To calibrate potentiometer.
a
To calibrate potentiometer.
an
voltmeter
by
using
a
ammeter
by
using
a
To calibrate an ammeter and a voltmeter by using a potentiometer. To determine the low resistance of the given coil by Carey foster bridge. To determine the value of two unknown resistances by using a potentiometer and verify the law of combination of resistances in series or parallel.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 4
DATED : _______________________
LIST OF EXPERIMENTS PRACTICAL [ IV ] To determine the work function of a metal by using a sodium light. To determine the ionization potential of mercury. To study the characteristics of an RLC series or acceptor circuit by plotting a response curve. Determine the resonant frequency , band width and Q factor of the circuit To study the characteristics of an RLC parallel or rejector circuit by plotting a response curve. Determine the resonant frequency , band width and Q factor of the circuit To plot the characteristics curve of a semi conductor diode. Determine the forward and reverse impedances [Resistances]. To study the static characteristics of a given transistor in common emitter mode. To set up half and full wave rectifier and study their waveforms on an oscilloscope. Also study the effect of smoothing circuit ( filter circuit ) on ripple voltage. To determine the Plank’s constant by using a spectrometer and hydrogen discharge tube. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 5
DATED : _______________________
EXPERIMENT NO .1 OBJECT: To determine the unknown resistance by using a neon flash lamp and a capacitor. APPARATUS: Neon flash lamp , Capacitor , Unknown resistance, D.C main supply , Stop watch. THEORY: The capacitor C is charged through the resistance R until the potential difference across capacitor attains the striking voltage VS of the neon bulb. At this voltage the neon gas in the bulb ionizes and begins to emit light. The capacitor then begins to discharge through the neon bulb until it’s potential difference is reduced to the value of Ve known as the extinction voltage at which the ionization and emission of light from the neon bulb is stop. This gives rise to a flash of light. and we get flashes of light one after other. The time between two consecutive flashes is known as flashing time. Let t1 be the time for the capacitor to charge up to V S volt and t 2 be the time for the capacitor to charge up to Ve . Since the relation between the voltage V across the capacitor after t seconds and the – 1 / CR applied voltage V0 is V = V0 [ 1 – e ]
t
1
V 0 CR log [ ] , t 2 V V e s
Flashing Period T
ASIFJAH ZEHRAVI
[ t - t ] 1 2
V 0 CR log [ ] V V e s
CR log [
V V e ] 0 V V e s
CELL 0300 – 2568922 & 0341 – 6623062 6
DATED : _______________________
CIRCUIT DIAGRAM:
OBSERVATIONS: Least count of stop watch = _______________ sec S. No.
Resistance R Ohms
Time for 10 flashes
Mean Time
Sec
1
2
3
Sec
Flashing Period T = t / 10 Sec
1. 2. 3. 4. 5. 6. 7. 8. 9. 10.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 7
DATED : _______________________
CALCULATIONS:
RESULT: The unknown resistance by using a neon flash lamp is calculated to be ______________________ Ohms.
PRECAUTION: Least count of stop watch should be noted and graduation on stopwatch should be studied carefully before starting the experiment. The applied voltage should be kept constant through out the experiment. The capacitance of the capacitor should be selected so as to get a measureable rate of flashing with the unknown resistance. In order to avoid error due to photo electric effect the experiment should be performed in a dark room or the neon bulb may be enclosed in a box with a small sighting hole. The DC mains voltage should be greater than the striking voltage for the lamp. Reading for time and striking voltage should be noted at at the instant when the lamp just glows. The stop watch should be started at the same time when DC mains is switched on. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 8
DATED : _______________________
SOURCES OF ERROR :
Inaccuracy of stopwatch. Loose connections Voltage flections. Necked wire should not be touched when the switch is on. Before starting the experiment get the circuit checked by your teacher
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 9
DATED : _______________________
EXPERIMENT NO . 2 OBJECT: To convert the given galvanometer in to an ammeter up to the range [ 0 – 1 ] ampere. APPARATUS: Galvanometer, Voltmeter, Ammeter, Resistance Box , Rheostat , Screw Gauge , 0ne way Key , Connecting Wires , Shunt Wire and Battery. THEORY: A galvanometer having a resistance Rg gives a full scale deflection when a current Ig is passed through it.. It can be converted in to an ammeter up to the range [ 0 – 1 ] ampere by connecting a small suitable resistance RS in parallel to it. The value of the shunt resistance RS is such that when this parallel combination of galvanometer and shunt resistance S is connected in series with a circuit carrying a current I , it allows a current Ig to pass through the galvanometer and the rest of the current [ I – Ig ] through the attached shunt resistances. The Rg ( The resistance of galvanometer ) and Ig ( Current for full scale deflection ) can be calculated by the following formulas. R R V H S I R g g [ R R ] R _ R g H S The value of the shunt resistance RS can be calculated by equating the potential differences across the two branches of the circuit. Let Rg and RS be the resistances of galvanometer and shunt resistance respectively ans let Ig and IS be the current passing through them. Then
I Is
=
Ig
+
Is
= [ I – Ig ]
_________ [ 1 ] _________ [ 2 ]
Since Rg and RS are in parallel then by Ohm’s law we have ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 10
DATED : _______________________
Is RS
=
Ig Rg
_________ [ 3 ]
From Equation [ 2 ] and Equation [ 3 ] we get RS
[ I – Ig ]
=
Ig R g
R g g R S [ I I ] g If the shunt wire has specific resistance and a radius r then it’s required length L is given by S π r2 L ρ I
WORKING FORMULA:
R H S R _ R H S
R
R g
1.
I R S
3.
R g g [ I I ] g
2.
3.
V
I g
L
[ R
H
R ] g
S π r2 ρ
Where Rg is the resistance of the given galvanometer RH is the high Resistance RS is the shunt Resistance Ig is the current for full scale deflection flowing through the galvanometer V is the range of ammeter up to which the galvanometer is to be converted RS is the shunt resistance connected in parallel. L is the length of wire having the resistance RS .
is the ratio of the circumference of a circle to its diameter
[ It is a mathematical constant whose value is 3.142 ] r is the radius of the wire. is the specific resistance of the material of the wire ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 11
DATED : _______________________
CIRCUIT DIAGRAM:
OBSERVATIONS: High Resistance RH
Full Deflection
Half Shunt R R Deflection Resistance H S R RS g R _ R H
Ohms
Divisions
Divisions
Ohms
S
Ohms
1. Least count of standard ammeter = ____________ Ampere __________Divisions of galvanometer = _________ Ampere One divisions of galvanometer = ___ / ___ = ___ Ampere 2. Least count of converted ammeter = ____________ Ampere VERIFICATION: S. No.
Standard Ammeter Reading Amperes
Reading of the shunted galvanometer Galvanometer Converted Divisions Ammeter Divisions
Amperes
Difference
Amperes
1. 2. 3. 4. 5. 6.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 12
DATED : _______________________
CALCULATIONS:
R H S R _ R H S
R
R g
1.
I R S
3.
R g g [ I I ] g
2.
3.
V
I g
L
[ R
H
R ] g
S π r2 ρ
RESULT: a. The given galvanometer has been converted in to an ammeter up to the range [ 0 – 1 ] ampere. PRECAUTION:
All connections should be neat and tight. Short and thick connecting wires should be used. The plugs of resistance box should be tight in their gaps. While finding the current IG for full scale deflection do not close the circuit with out introducing a high resistance by the resistance box. No portion of calculated length of the wire should be under the binding screw s of the galvanometer. When comparing the readings of standard ammeter and the shunted galvanometer pass large currents to produce large deflection, thus reducing error in reading the deflection. Care should be taken in handling the apparatus. SOURCES OF ERROR : Loose connections Use of long and thin connecting wires may add more resistance in the circuit. For finding full scale deflection if the circuit is closed with out introducing a high resistance by the resistance box. The portion of calculated length of the wire should out of the binding screw of the galvanometer. A small amount of current may cause the error in the deflection of the galvanometer. Loose plugs in the resistance box. Fluctuation of current in the circuit. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 13
DATED : _______________________
EXPERIMENT NO . 3 OBJECT: To convert the given galvanometer in to an voltmeter up to the range [ 0 – 1 ] volt. APPARATUS: Galvanometer , Voltmeter , Ammeter , Resistance Box , Rheostat , 0ne way Key , Connecting Wires and a Battery. THEORY: A galvanometer having a resistance Rg gives a full scale deflection when a current Ig is passed through it.. It can be converted in to a voltmeter up to the range [ 0 – 1 ] volt by connecting a suitable resistance RX in series with it. The value of the series resistance RX is such that it allows a current Ig to pass through the combination of galvanometer and series resistance RX when potential difference V is applied across it. By applying Ohm’s law the value of RX is given by
R H S I R g g [ R R ] R _ R g X H S To convert a moving coil galvanometer in to a voltmeter up to a maximum voltage EX it is necessary to connect a high resistance in series with the galvanometer coil of the resistance Rg Most of the potential drop will then occur across the resistance RX The value of the series resistance RX should be so adjusted that the voltage E produces across the galvanometer coil and the series resistance RX a current Ig sufficient to produce full scale deflection in the galvanometer movement . Then by Ohm’s law R
V
V
=
Ig [ R X + R g ]
Ig R X + I g R g
= V
Ig R X = V – Ig R g ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 14
DATED : _______________________
V R
R
X
I
X
g I
V I g
X
R
- I R g g
R
g I
g
g
V I
g
R g
WORKING FORMULA:
1.
3. R
R H S R _ R H S
R
R g
X
2.
I g
V [ R R ] g
V I
g
R g
Where Rg is the resistance of the given galvanometer RH is the high Resistance RS is the shunt Resistance Ig is the current for full scale deflection flowing through the galvanometer V is the range of voltmeter up to which the galvanometer is to be converted RX is the high Resistance connected in series. CIRCUIT DIAGRAMS:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 15
DATED : _______________________
OBSERVATIONS: High Resistance RH
Full Deflection
Ohms
Divisions
Half Shunt R R Deflection Resistance H S R RS g R _ R H
Divisions
1. Least count of standard voltmeter
Ohms
S
Ohms
= ___________ Ampere
_________Divisions of galvanometer = ____________ Volts One divisions of galvanometer = ____ / ____ = ______ Volts 2. Least count of converted ammeter
= ____________ Volts
VERIFICATION: S. No.
Standard Voltmeter Reading Volts
Reading of the shunted galvanometer Galvanometer Converted Divisions Voltmeter Divisions
Difference
Volts
Volts
1. 2. 3. 4. 5. 6. CALCULATIONS:
1. R
g
3.
R
X
R H S R _ R H S V I g
R
ASIFJAH ZEHRAVI
2. I
g
V [ R R ] g
R g
CELL 0300 – 2568922 & 0341 – 6623062 16
DATED : _______________________
RESULT: b. The given galvanometer has been converted in to a voltmeter up to the range [ 0 – 1 ] volts. PRECAUTION:
All connections should be neat and tight. Short and thick connecting wires should be used. The plugs of resistance box should be tight in their gaps. While finding the current IG for full scale deflection do not close the circuit with out introducing a high resistance by the resistance box. No portion of calculated length of the wire should be under the binding screw s of the galvanometer. When comparing the readings of standard ammeter and the shunted galvanometer pass large currents to produce large deflection, thus reducing error in reading the deflection. The rheostat used as potential divider should not be of low resistance. Care should be taken in handling the apparatus.
SOURCES OF ERROR : Loose connections Use of long and thin connecting wires may add more resistance in the circuit. For finding full scale deflection if the circuit is closed with out introducing a high resistance by the resistance box. The portion of calculated length of the wire should out of the binding screw of the galvanometer. A small amount of current may cause the error in the deflection of the galvanometer. A low resistance rheostat as potential divider may be used. Loose plugs in the resistance box. Fluctuation of current in the circuit.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 17
DATED : _______________________
EXPERIMENT NO . 4 OBJECT: To calibrate a voltmeter by using a potentiometer. APPARATUS: Potentiometer , Jockey , Two Rheostat , Two Battery ,Two 0ne way Key , Galvanometer , Two way key , Voltmeter , Standard cell and Connecting Wires. THEORY: A galvanometer WORKING FORMULA:
V S
E S
[
L
2 L 1
]
Where VS is the calculated voltage ES is the E.M.F of standard cell L1 is the balancing length for Standard cell is in circuit L2 is the balancing length for R 2 is in circuit CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 18
DATED : _______________________
OBSERVATIONS: 3. Least count of standard voltmeter 4. E .M . F of standard cell
= _____________ Volts
= E S = _______________ Volts
5. Balancing length when Standard cell is in circuit L1 = __ cm.
S. Balancing No length for R 2 is in circuit
Calculated Voltage
V E [ S S
L
2 L 1
]
Voltmeter Reading
Difference
V
[ VS – V ]
volts
volts
L2 cm
volts
1. 2. 3. 4. 5.
CALCULATIONS:
V S
E S
[
L
2 L 1
]
RESULT: The given voltmeter has been calibrated a by using a potentiometer
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 19
DATED : _______________________
PRECAUTION:
All connections should be neat and tight. Short and thick connecting wires should be used. The jockey must have sharp edge. Avoid the sliding of jockey on the wire rather it should be gently tapped over it. The current through the potentiometer should be passed while taking readings.. The plugs of resistance box should be tight in their gaps. Positive terminal of the batteries B1 & B2 and standard ES cell should be connected to the same end of the potentiometer wire. Emf of the battery B1 should be greater than emf of the battery B2 or the standard cell. The rheostat R 1 once set should not be changed through out the experiment. Care should be taken in handling the apparatus.
SOURCES OF ERROR : Loose connections Error due to the sliding of jockey on the wire. Use of long and thin connecting wires may add more resistance in the circuit. Loose plugs in the resistance box. Jockey may not be of sharp edge. Fluctuation of current in the circuit.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 20
DATED : _______________________
EXPERIMENT NO . 5 OBJECT: To calibrate an ammeter by using a potentiometer. APPARATUS: Potentiometer , Jockey , Two Rheostat , Two Battery ,Two 0ne way Key , Galvanometer , Two way key , Ammeter , Standard cell , Resistance box and Connecting Wires. THEORY: A galvanometer WORKING FORMULA:
I S
[
E R
S S
L
2 L 1
]
Where VS is the calculated voltage ES is the E.M.F of standard cell RS is the standard resistance. VS is the calculated current L1 is the balancing length for Standard cell is in circuit L2 is the balancing length for R 2 is in circuit
CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 21
DATED : _______________________
OBSERVATIONS: 6. Least count of standard ammeter 7. E .M . F of standard cell
= ___________ Ampere
= E S = ______________ Volts
8. Value of standard resistance = RS = ____________ Ohms 9. Balancing length when Standard cell is in circuit L1 ___ cm
S. Balancing Calculated Current No length for L E R S is in 2 S I [ ] circuit S
L2
cms
R
Ammeter Reading
[ IS – I ]
I
L 1
S
amp
Difference
amp
amp
1. 2. 3. 4. 5.
CALCULATIONS:
I S
[
E R
S S
L
2 L 1
]
RESULT: The given ammeter has been calibrated a by using a potentiometer
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 22
DATED : _______________________
PRECAUTION:
All connections should be neat and tight. Short and thick connecting wires should be used. The jockey must have sharp edge. Avoid the sliding of jockey on the wire rather it should be gently tapped over it. The current through the potentiometer should be passed while taking readings.. The plugs of resistance box should be tight in their gaps. Positive terminal of the batteries B1 & B2 and standard ES cell should be connected to the same end of the potentiometer wire. Emf of the battery B1 should be greater than emf of the battery B2 or the standard cell. The rheostat R 1 once set should not be changed through out the experiment. Care should be taken in handling the apparatus.
SOURCES OF ERROR : Loose connections Error due to the sliding of jockey on the wire. Use of long and thin connecting wires may add more resistance in the circuit. Loose plugs in the resistance box. Jockey may not be of sharp edge. Fluctuation of current in the circuit.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 23
DATED : _______________________
EXPERIMENT NO . 6 OBJECT: To calibrate an ammeter and a voltmeter by using a potentiometer. APPARATUS: Potentiometer , Jockey , Two Rheostat , Two Battery ,Two 0ne way Key , Galvanometer , Two way key , Ammeter , Voltmeter , Standard cell , Resistance box and Connecting Wires. WORKING FORMULA:
V S
E S
[
L
2 L 1
] ,
I S
[
E R
S S
L
2 L 1
]
Where VS is the calculated voltage ES is the E.M.F of standard cell RS is the standard resistance. L1 is the balancing length for Standard cell is in circuit L2 is the balancing length for R 2 is in circuit CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 24
DATED : _______________________
OBSERVATIONS: 1. Least count of standard ammeter
= ______ Ampere
2. Least count of standard voltmeter
=_________ Volts
3. E .M . F of standard cell
= E S = __________ Volts
4. Value of standard resistance = RS = _______ Ohms. 5. Balancing length when Standard cell is in circuit L1 = ___ cm S. Balancing No Length when R S is in circuit
Voltage
VS
Voltmeter Reading
Current
IS
V
Ammeter Reading
Difference
Difference
I
[ VS – V ]
[ IS – I ]
amps
volts
amps
L2 cms
volts
volts
amps
1. 2. 3. 4. 5.
CALCULATIONS:
V S
E S
[
L
2 L 1
]
,
I S
[
E R
S S
L
2 L 1
]
RESULT: The given ammeter and voltmeter have been calibrated a by using a potentiometer ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 25
DATED : _______________________
PRECAUTION:
All connections should be neat and tight. Short and thick connecting wires should be used. The jockey must have sharp edge. Avoid the sliding of jockey on the wire rather it should be gently tapped over it. The current through the potentiometer should be passed while taking readings.. The plugs of resistance box should be tight in their gaps. Positive terminal of the batteries B1 & B2 and standard ES cell should be connected to the same end of the potentiometer wire. Emf of the battery B1 should be greater than emf of the battery B2 or the standard cell. The rheostat R 1 once set should not be changed through out the experiment. Care should be taken in handling the apparatus.
SOURCES OF ERROR : Loose connections Error due to the sliding of jockey on the wire. Use of long and thin connecting wires may add more resistance in the circuit. Loose plugs in the resistance box . Jockey may not be of sharp edge . Fluctuation of current in the circuit.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 26
DATED : _______________________
EXPERIMENT NO . 7 OBJECT: To determine the low resistance of the given coil by Carey foster bridge. APPARATUS: Meter bridge, Galvanometer, Two resistance boxes, Given coil , Fractional resistance box , Cell, One way key and Connecting wires. THEORY: Carey foster bridge is a modified form of meter bridge having four gaps across which resistances X , P , Q , and Y are connected. P and Q are two equal resistances X is the unknown low resistance and Y is the known resistance. If the balance point C is obtained at a point L 1 cm from the end A , then X L ρ α P 1 - - - - - - - - - - - -[ i ] Q Y [ 100 L ] ρ β 1 Where is the resistance per cm length of the wire and and are the end resistance at A and B respectively. If X and Y are interchanged and the balance point is obtained at point L 2 from the end A then Y L ρ α P 2 - - - - - - - - - - - -[ ii ] Q X [ 100 L ] ρ β 2 From equation [ I ] and equation [ ii ] X L ρ α Y L ρα P 1 2 PQ X Y 100 ρ β X Y 100 ρ α β As the denominator s are equal therefore X + L1 + =
Y + L2 +
X–Y =
L1 + – [L2 + ]
X–Y =
L1 + – L2 –
X–Y =
[L1 – L2 ]
X = Y +
[ L 1 – L 2 ] -------------------- [ iii ]
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 27
DATED : _______________________
Thus X can be determined if L 1 , L 2 and are known For finding the resistance per cm of the wire , make X = 0 by closing gap NO 1 by a copper shorting strip and balance point is obtained at L 1. Now copper strip X and Y are interchanged and the balance point is obtained at L 2 then equation [ iii ] can be written as 0 = Y +
[L1 – L2 ]
[L1 – L2 ]
= Y
ρ
Y [ L L ] 1 2
WORKING FORMULA:
ρ
Y [ L L ] 1 2
,
X = Y + [L2–L1]
Where is the resistance per cm length of the given wire X is the unknown low resistance. Y is the known resistance. L 1 is the balance point from end A L 2 is the balance point from end A when X and Y are interchanged CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 28
DATED : _______________________ FOR DETERMINATION OF
OBSERVATIONS:
[ The resistance per cm of the wire ] Resistance P S. NO
Y
= _____ Ohms , Resistance P Distance of balancing point from A with shorting strip in
Ohm
L1
L2
cm
cm
ρ
= ______ Ohms Y [L L ] 1 2
Ohm
1. 2. 3.
OBSERVATIONS: FOR DETERMINATION OF UNKNOWN LOW RESISTANCE
Resistance P S. NO
Y
= _____ Ohms , Resistance P Distance of balancing point from end A
Ohm
L1
L2
cm
cm
= _____ Ohms
X = Y + [ L 2 – L 1]
Ohm
1. 2. 3.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 29
DATED : _______________________
CALCULATIONS:
ρ
Y [ L L ] 1 2
Actual Value =
,
X = Y + [L2–L1]
____________________ Ohms
Percentage Of Error
Actual Value Calculated Value Actual Value
100
RESULT: c. The unknown low resistance of the given coil by Carey foster bridge is calculated to be ______________ Ohms. PRECAUTION:
All connections should be neat and tight. Short and thick connecting wires should be used. The jockey must have sharp edge. Avoid the sliding of jockey on the wire rather it should be gently tapped over it. The current through the bridge should be disconnected while reversing the key. The current through the potentiometer should be passed while taking readings.. The plugs of resistance box should be tight in their gaps. Care should be taken in handling the apparatus.
SOURCES OF ERROR : Loose connections Error due to the sliding of jockey on the wire. Use of long and thin connecting wires may add more resistance in the circuit. Loose plugs in the resistance box . Jockey may not be of sharp edge . Fluctuation of current in the circuit.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 30
DATED : _______________________
EXPERIMENT NO . 8 OBJECT: To determine the value of two unknown resistances by using a potentiometer and verify the law of combination of resistances in series or parallel. APPARATUS: Potentiometer , Jockey , Two Rheostat , Battery ,Two 0ne way Keys , Galvanometer , Two way key , Resistance box , Two unknown resistances , Two cells and Connecting Wires.
WORKING FORMULA:
r
R
[ L L ] 2 1 L 1
Where r is the unknown resistance. R is the known resistance. L1 is the balancing length for R. L2 is the balancing length for ( R + r ).
CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 31
DATED : _______________________
OBSERVATIONS: Known Un known Balancing balancing Resistance Resistance length for length for R r
R
(R+r)
L1
L2
Un known Resistance
r R[ L
2 L
Ohms
Ohms
Cm
Cm
Mean Un known Resistance
r
L ] 1 1
Ohms
Ohms
r1
r2
r1 + r2
1 1 r r 1 2
CALCULATIONS:
r
R
[ L L ] 2 1 L 1
r1 + r2 1 1 r r 1 2
RESULT: Un known resistance r
1
=
____________ Ohms
Un known resistance r
2
=
____________ Ohms
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 32
DATED : _______________________
For series combination Observed value [ r 1 + r 2 ]
=
____________ Ohms
Calculated value [ r 1 + r 2 ]
=
____________ Ohms
For parallel combination Observed value [ r1 r1 ] 1
Calculated value [ r1
1
=
____________ Ohms
=
____________ Ohms
2
1 r 2
]
PRECAUTION: All connections should be neat and tight. Short and thick connecting wires should be used. The positive terminal of the battery and that of cell must be connected to the terminal on zero side of the potentiometer. The emf of the main battery E1 should be greater than E 2 used. Never insert K1 & K2 simultaneously. The current should remain constant for each set of observation. The current should be passed only for the duration it is necessary otherwise the balance point will keep on changing. The jockey must have sharp edge. Avoid the sliding of jockey on the wire rather it should be gently tapped over it. Care should be taken in handling the apparatus. The plugs of resistance box should be tight in their gaps. SOURCES OF ERROR : Loose connections. Error due to the sliding of jockey on the wire. Use of long and thin connecting wires may add more resistance in the circuit. Loose plugs in the resistance box . Jockey may not be of sharp edge . Fluctuation of current in the circuit. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 33
DATED : _______________________
EXPERIMENT NO . 9 OBJECT: To determine the work function of a metal by using a sodium light. APPARATUS: Photo electric cell , Sodium light , Battery , Rheostat , One Way key , Four way key or Reversing key , Micro ammeter , Voltmeter and Connecting wires. WORKING FORMULA:
Work Function
Φ
h
c λ
- V e, 0
Where is the function of the given metal. h is the Plank’s Constant c is the velocity of light is the wavelength of sodium light V0 is the stopping potential e is the charge on an electron. CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 34
DATED : _______________________
OBSERVATIONS: Least count of voltmeter = ________________________ volts. Least count of micro ammeter = ____________________ amp. S. NO
Distance of sodium lamp from Photo cell _____________cm Voltmeter Micro ammeter reading reading Volts
Divisions
1. 2. 3. 4. 5. 6. 7. 8. 9. 10.
CALCULATIONS:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 35
DATED : _______________________
Stopping potential from the graph V0 = ________________ volt. Plank’s Constant = h = 6.625 × 10 – 34 joules – sec Velocity of light = c = 3 × 10 8 m / sec. or 3 × 10 10 cm / sec. Wavelength of sodium light = = 5893 Å = 5893 × 10 – 10 m Charge on an electron = e = 1.6 × 10 – 19 coul.
Work Function
Actual Value =
Φ
h
c λ
- V e 0
____________________ Ohms
Percentage Of Error
Actual Value Calculated Value Actual Value
100
RESULT: The work function of a metal by using a sodium light is calculated to be _______________________ Electron volts. PRECAUTION: All the connections should be tight and clean. Distance between the source and the photo-cell should be kept unchanged for one set of observations. The applied voltage should be changed in small and regular steps. A V.T.V.M. if available, should be used in place of voltmeter. To increase the life of the photo-cell, its window should be closed, when it is not in use. SOURCES OF ERROR : Loose connections Change of distance between the source and the photocell during the experiment. Voltage flections Use of a simple voltmeter. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 36
DATED : _______________________
EXPERIMENT NO . 10 OBJECT: To determine the ionization potential of mercury. APPARATUS: A mercury diode with base, Voltmeter, Micro ammeter, Rheostat , One Way key , Power supply and Connecting wires. THEORY: The breaking of an atom in an electron and positively charged ions is called ionization. Ionization can be brought about by bombarding an atom by fast moving particles such as electrons. The electron must be accelerated to certain definite energy for given type of atoms. It will be seen that electron having sufficiently energy can break off the loosely leave outermost electrons of the target atom. This will correspond to a sudden increase in plate current. The ionization potential is therefore defined as the maximum accelerating potential which is required to accelerate the electrons so that they can ionize the target. CIRCUIT DIAGRAM:
OBSERVATIONS: Least count of voltmeter = ________________________ volts. Least count of micro ammeter = ____________________ amp.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 37
DATED : _______________________
S. Anode Voltage Anode Current NO [ Plate Voltage ] [ Plate Current ] Volts Amp 1. 2. 3. 4. 5. 6. 7. 8.
CALCULATIONS:
Actual Value =
____________________ Volts
Percentage Of Error
Actual Value Calculated Value Actual Value
100
RESULT: The ionization potential of mercury is calculated to be _______________________ Volts. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 38
DATED : _______________________
PRECAUTION: The connections should be tight and clean. The current passed through the filament should not be more than its related value. A high resistance voltmeter should be preferred. If the anode current is larger, use a milli ameter in place of micro ammeter. SOURCES OF ERROR : Loose connections Use of low resistance voltmeter. Voltage flections
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 39
DATED : _______________________
EXPERIMENT NO . 11 OBJECT: To set up half and full wave rectifier and study their waveforms on an oscilloscope. Also study the effect of smoothing circuit ( filter circuit ) on ripple voltage. APPARATUS: Four point contact diodes , 6V step down transformer , A high resistance of 10 Kilo Ohms , Capacitor , Inductors, Cathode Ray Oscilloscope. THEORY : The conversion of an alternating current in to direct current is called rectification. This is very conveniently achieved by diodes. A circuit which is used for rectification is called a rectifier. To make the out put waveform from a study voltage we use a suitable combination of capacitor and inductor in the circuit which are known as filters. The equation for ripple factor is given 1 ---------------------- [ 1 ] Ripple Factoe R . F 4 3 fr C R
1
Ripple Factoe R . F 4
Ripple Factoe R . F
4
120 1000 10 - 6 300 1 3 12 3
3
Ripple Factoe R . F 0 . 004 I Ripple Factoe R . F ( rms ) 2 1 -------------------- [ 2 ] I d.c Where I r m s = Root mean square value of A.C current I d.c = Value of D.C current For full wave rectification Integrating equation I T I rms i 2 dt 0 and I d.c 2 0 For half wave rectification the values of I as under I rms 0 and I d.c 2 ASIFJAH ZEHRAVI
[ 2 ] we get 2 I T 0 i dt π 0
I r m s and I d .c are given I 0 π
CELL 0300 – 2568922 & 0341 – 6623062 40
DATED : _______________________
FOR HALF WAVE RECTIFICATION Now putting the values of I r m s and I d .c in equation [ 2 ] we get I 0 Ripple Factoe R . F ( 2 )2 1 I 0 π
Ripple Factoe R . F Ripple Factoe R . F R . F = 1 . 211
(
)2 1
2 1. 4680
FOR HALF WAVE RECTIFICATION Now putting the values of I r m s and I d .c in equation [ 2 ] we get I 0 2 )2 1 Ripple Factoe R . F ( 2I 0 π
Ripple Factoe R . F Ripple Factoe R . F R . F = 0 . 483
(
2 2 0 . 2340
)2 1
CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 41
OBSERVATIONS:
DATED : _______________________
FOR HALF WAVE RECTIFIER SHAPE OF WAVE FORM In Put Waveform
Out Put Waveform Un filtered
Peak value = E0 = _____ Volts
Peak value = E0 = _____ Volts
SHAPE OF WAVE FORM WHEN DIODE IS INVERTED In Put Waveform
Peak value = E0 = _____ Volts
Out Put Waveform Un filtered
Peak value = E0 = _____ Volts
SHAPE OF WAVE FORM WHEN DIODE IS INVERTED In Put Waveform
Out Put Waveform Filtered
Peak value = F0 = _____ Volts d.c out put = F0 = _____ Volts
Peak value = F0 = _____ Volts d.c out put = F0 = _____ Volts
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 42
DATED : _______________________
FOR FULL WAVE RECTIFIER SHAPE OF WAVE FORM In Put Waveform
Out Put Waveform Un filtered
Peak value = E0 = _____ Volts
Peak value = E0 = _____ Volts
SHAPE OF WAVE FORM WHEN DIODE IS INVERTED In Put Waveform
Peak value = E0 = _____ Volts
Out Put Waveform Un filtered
Peak value = E0 = _____ Volts
SHAPE OF WAVE FORM WHEN DIODE IS INVERTED In Put Waveform
Out Put Waveform Filtered
Peak value = F0 = _____ Volts d.c out put = F0 = _____ Volts
Peak value = F0 = _____ Volts d.c out put = F0 = _____ Volts
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 43
DATED : _______________________
CALCULATIONS Actual Value =
____________________ Volts
Percentage Of Error
Actual Value Calculated Value Actual Value
100
RESULT: The waveforms of half and full wave rectifier on an oscilloscope have been studied. PRECAUTION: Care should be taken in connecting the diodes whose N-type ends is marked with red spot or arrow. V.T.V.M. and C.R.O. must be earthed properly. While observing input waveform crystal diodes must be disconnected. SOURCES OF ERROR : Loose connections The N – type ends of diodes are not marked properly Voltage flections
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 44
DATED : _______________________
EXPERIMENT NO . 12 OBJECT: To study the characteristics of an RLC series or acceptor circuit by plotting a response curve. Determine the resonant frequency , band width and Q factor of the circuit APPARATUS: Voltmeter, Micro ammeter, Rheostat , One Way key , Power supply and Connecting wires. WORKING FORMULA:
Resonant Frequency
Band Width
fr
1 2 π
LC
Δf f f 2 1
Quality Factor Q factor
Resonant Frequency Band Width
Where f r is the resonant frequency. L is the inductance. C is the capacitance. f is the band width. f 1 & f 2 are the frequencies where the response falls to 0.707 of it’s maximum value. CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 45
f r f
DATED : _______________________
OBSERVATIONS: Resistance R = _______ Ohms. Inductance L =________ m Henry =________ Henry Capacitance C = ______ f. = ___________ Farad. S. Frequency ( f ) Current in the circuit NO CPS or HZ Amp 01. 02. 03. 04. 05. 06. 07. 08. 09. 10.
Log f
CALCULATIONS: fr
1 2 π
Actual Value =
LC
Δf f f 2 1
Q factor
f r f
____________________ Volts
Percentage Of Error
ASIFJAH ZEHRAVI
Actual Value Calculated Value Actual Value
100
CELL 0300 – 2568922 & 0341 – 6623062 46
DATED : _______________________
RESULT: The characteristics of an acceptor circuit have been studied. It is seen that we get maximum output when the resonant frequency is applied across the series combination of L , C and R. The resonant frequency f r is calculated to be _______ hertz. The calculated value of resonant frequency is near about the observed value. The value of inductance L in the circuit is calculated to be __________Henry. Band width f = ____ hertz and Q – factor = _________ PRECAUTION: Suitable set of inductance (L) and capacitance (C) should be selected and their values should be known. The connection should be tight and clean. The AVO meter should be adjusted for suitable range before switching on the circuit. The selected range of the AVO meter should not be changed for the whole set of observations. Frequency from the oscillator should be changed in regular small steps. The naked wires should not be touched, when the circuit is on. SOURCES OF ERROR :
Loose connections Voltage flections. Necked wire should not be touched when the switch is on. Before starting the experiment get the circuit checked by your teacher
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 47
DATED : _______________________
EXPERIMENT NO . 13 OBJECT: To study the characteristics of an RLC parallel or rejector circuit by plotting a response curve. Determine the resonant frequency , band width and Q factor of the circuit APPARATUS: Voltmeter, Micro ammeter, Rheostat , One Way key , Power supply and Connecting wires.
WORKING FORMULA:
Resonant Frequency
Band Width
fr
1 2 π
LC
Δf f f 2 1
Quality Factor Q factor
Resonant Frequency Band Width
Where f r is the resonant frequency. L is the inductance. C is the capacitance. f is the band width. f 1 & f 2 are the frequencies where the current rises to 1.414 times of the minimum current CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 48
f r f
DATED : _______________________
OBSERVATIONS: Resistance R = _______ Ohms. Inductance L =________ m Henry =________ Henry Capacitance C = ______ f. = ___________ Farad. S. Frequency ( f ) Current in the circuit NO CPS or HZ Amp 01. 02. 03. 04. 05. 06. 07. 08. 09. 10.
Log f
CALCULATIONS: fr
1 2 π
LC
ASIFJAH ZEHRAVI
Δf f f 2 1
f Q factor r f
CELL 0300 – 2568922 & 0341 – 6623062 49
DATED : _______________________
Actual Value =
____________________ Volts
Percentage Of Error
Actual Value Calculated Value Actual Value
100
RESULT: The characteristics of an rejector circuit have been studied. It is seen that we get minimum output when the resonant frequency is applied across the parallel combination of L , C and R. The resonant frequency f r is calculated to be _______ hertz. The calculated value of resonant frequency is near about the observed value. The value of inductance L in the circuit is calculated to be __________Henry. Band width f = ____ hertz and Q – factor = _________ PRECAUTION: Suitable set of inductance (L) and capacitance (C) should be selected and their values should be known. The connection should be tight and clean. The AVO meter should be adjusted for suitable range before switching on the circuit. The selected range of the AVO meter should not be changed for the whole set of observations. Frequency from the oscillator should be changed in regular small steps. The naked wires should not be touched, when the circuit is on. SOURCES OF ERROR :
Loose connections Voltage flections. Necked wire should not be touched when the switch is on. Before starting the experiment get the circuit checked by your teacher
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 50
DATED : _______________________
EXPERIMENT NO . 14 OBJECT: To plot the characteristics curve of a semi conductor diode. Determine the forward and reverse impedances [Resistances]. APPARATUS: Voltmeter, Micro ammeter, Rheostat , One Way key , Power supply and Connecting wires. CIRCUIT DIAGRAM:
OBSERVATIONS:
Least count of voltmeter = ______________________ volts. Least count of micro ammeter = __________________ amp. Least count of milli ammeter = ___________________ m amp. S. NO
Forward Bias Voltage Volt
Current Milli ampere
Reverse Bias Voltage Volt
Voltage Microampere
01. 02. 03. 04. 05. 06. 07. 08. 09. 10. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 51
DATED : _______________________
CALCULATIONS:
Actual Value =
____________________ Volts
Percentage Of Error
Actual Value Calculated Value Actual Value
100
RESULT: The characteristic curves for a ( p – n ) junction ( both for forward bias and reverse bias ) have been drawn. It is seen that when the junction is forward biased with a small potential difference it allows large current (in milli amperes ) but when it is reverse biased with a large potential difference small current ( in micro amperes ) passed through it PRECAUTION: The connections should be neat clean and tight. The AVO meter should be adjusted for suitable range before switching on the circuit. The applied voltage never exceed the rated value of the semi conductor diode. Care should be taken in connecting the diode whose N – type end is marked with red spot or arrow. Voltage should be changed in small and regular steps. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 52
DATED : _______________________
The naked wires should not be touched, when the circuit is on. SOURCES OF ERROR : Loose connections Voltage flections. The applied voltage exceed the rated value of the semi conductor diode. Necked wire should not be touched when the switch is on. Before starting the experiment get the circuit checked by your teacher
\ ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 53
DATED : _______________________
EXPERIMENT NO . 15 OBJECT: To study the static characteristics of a given transistor in common emitter mode. APPARATUS: Given transistor ( provided with base resistance , also called biasing resistance ), Micro ammeter, Milli ammeter , A small Power supply, Two Way key and Voltmeter THEORY: A transistor consists of germanium or silicon crystal in which a layer of N – type germanium is sand witched between two layers of P – type germanium. This is forming as P – N – P transistor. Similarly a transistor in which a layer of P – type germanium is sad witched between the two layers of N – type germanium is called N – P – N transistor. A transistor consists of three parts which are emitter , base and collector. The transistor can be connected in the circuits normally in three ways. Common – Emitter configuration Common – Base configuration Common – Collector configuration First one is forward biased junction. The second is reverse bias junction. A junction is said to be forward biased if the positive terminal of the battery is connected to the P – type region and the negative terminal is connected to the N – type region of transistor. Similarly if the positive terminal of the battery is connected to the N – type region and the negative terminal is connected to the P – type region of transistor is called reverse biased junction. CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 54
DATED : _______________________
OBSERVATIONS:
[ FOR INPUT CHARACTERISTICS ]
KEEPING COLLECTOR TO AMMETER VOLTAGE VCE IS CONCTANT S. VCE = 0 Volt VCE = 4 Volt VCE = 8 Volt NO
VBE Volt
IB Amp
VBE Volt
IB Amp
VBE Volt
IB Amp
01. 02. 03. 04. 05.
[ FOR OUTPUT CHARACTERISTICS ] [ KEEPING BASE CURRENT I B IS CONCTANT ] S. NO
I B = 0 A I B = 20 A I B = 40 A VCE IC Volt m A
VCE Volt
IC mA
VCE Volt
IC mA
I B = 60 A VCE IC Volt m A
01. 02. 03. 04. 05.
CALCULATIONS:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 55
DATED : _______________________
Actual Value =
____________________ Volts
Percentage Of Error
Actual Value Calculated Value Actual Value
100
RESULT: The input characteristic curves ( between VBE and IB keeping VCE is constant ) and output characteristic curves ( between VCE and IC keeping IB is constant ) have been drawn. It is seen from these curves that a small change in base current produces a large change in collector current IC. PRECAUTION: Do not apply base more than 3 volts and collector voltage more than 12 volts. Carefully observed the polarities of the power supplies and terminals of the transistor. Avoid rough handling the transistor otherwise it may be damaged. While making or breaking any connections both the power supplies should be disconnected. Before connecting a transistor in to a circuit one should carefully identify the base ,emitter and collector terminals. SOURCES OF ERROR :
Loose connections. Voltage fluctuation. Un correct connection of a transistor in the circuit. Base voltage may be more than 3 volts. Collector voltage may be bore than 12 volts. Necked wire should not be touched when the switch is on. Before starting the experiment get the circuit checked by your teacher
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 56
DATED : _______________________
EXPERIMENT NO . 16 OBJECT: To determine the Plank’s constant by using a spectrometer and hydrogen discharge tube. APPARATUS: Spectrometer ,Diffraction grating , Hydrogen discharge tube and Sprit level. WORKING FORMULA: Plank’s constant can be calculated as 1 1 1 2 π2 m e 4 k 2 λ Plank' s Constant h [ ( ) ] 3 C 2 2 2 n
λ
d Sin θ N
Where
h is the Plank’s constant m is the mass of the electron e is the charge of the electron k is the Coulomb’s constant for electrostatic force is the wave length of light n is the color of the spectral line d is the grating element is the angle of diffraction N is the order of image
OBSERVATIONS: 1. Least count of stop watch = 1 minute. 2. Number of lines ruled on the grating = ________lines / inch. 3. Grating element = d
1inch no of lines
2.54 cm [
4. Mass of an electron = m = 9.1072 × 10
= ______cm
] – 31
Kg.
5. Charge on an electron = e = 1.6 × 10 – 19 coul. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 57
DATED : _______________________
6. Coulomb’s constant for electrostatic force =k = 9 × 10 9 N – m 2 /coul 2 7. Speed of light = c = 3 × 10 8 m / sec. or 3 × 10 10 cm / sec. FOR RED SPECTRAL LINE S NO
Order Of Image
Lines Diffraction reading on Right Left side side [A] [B]
deg 1.
I
D1
2.
II
D2
deg
Difference Of Readings 2 = A – B
Angle of diffraction
Wave length
deg
deg
cm
Difference Of Readings 2 = A – B
Angle of diffraction
Wave length
deg
deg
cm
Difference Of Readings 2 = A – B
Angle of diffraction
Wave length
deg
deg
cm
FOR BLUE SPECTRAL LINE S NO
Order Of Image
Lines Diffraction reading on Right Left side side [A] [B]
deg 1.
I
D1
2.
II
D2
S NO
Order Of Image
Lines
deg
FOR VIOLET SPECTRAL LINE Diffraction reading on Right Left side side [A] [B]
deg 1.
I
D1
2.
II
D2
ASIFJAH ZEHRAVI
deg
CELL 0300 – 2568922 & 0341 – 6623062 58
DATED : _______________________
CALCULATIONS: Plank’s constant for red spectral line [ n = 3 ] 1 2 π2 m e 4 k 2 λ r 1 1 Plank' s Constant h [ ( ) ] 3 C 22 32 Plank’s constant for red spectral line [ n = 4 ] 1 2 π2 m e 4 k 2 λ 1 1 b Plank' s Constant h [ ( ) ] 3 C 2 2 2 4 Plank’s constant for red spectral line [ n = 5 ] 1 2 π2 m e 4 k 2 λ v 1 1 Plank' s Constant h [ ( ) ] 3 C 22 52 Actual Value = h = 6.625 × 10 – 34 J – s. Percentage Of Error
Actual Value Calculated Value Actual Value
100
RESULT: The Plank’s constant by using a spectrometer and hydrogen discharge tube is calculated to be ____________ J – s. PRECAUTION: All adjustment of the spectrometer must be correctly made. The grating should be adjusted in the vertical plane and the rulings on it should also be made vertical. In measuring the angle, the left of the image should coincide with the vertical cross-wire for positions of telescope on either side of the central image. The light should be incident on that side of the grating on which there is no rulings. This is done to obtain no refraction after deflection has taken place. SOURCES OF ERROR : Slit may mot sharp. Spectrometer may not be properly adjusted. Turn table may not be properly adjusted. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 59
