4 . b . sc. i i journel

Dated : _______________

ASIFJAH ZEHRAVI CELL 0300 – 2568922 & 0341 – 6623062

1

Dated : _______________


2

Name:_________________________________________ Class: _____________ Section:__________

Roll No: ________ Group:_______________________

Dated : _______________


3

Certified that Miss. / Mr._______________________________ Of class ____________ has carried out the necessary practical work as prescribed by the Board of Intermediate Education / University of Karachi for the year _____________________

__________________________________ ______________________________

Head of the department In charge

Date:__________________ Date:______________

Dated : _______________


4

S. No

Date

P. No

Initial

1

To determine the unknown resistance by using a neon flash lamp and a capacitor.

01

2

To convert the given galvanometer in to an ammeter up to the range [ 0 – 1 ] ampere.

05

3

To convert the given galvanometer in to an voltmeter up to the range [ 0 – 1 ] volt.

10

4

To calibrate a voltmeter by using a potentiometer.

15

5

To calibrate an ammeter by using a potentiometer.

18

6

To calibrate an ammeter and a voltmeter by using a potentiometer.

21

7

To determine the low resistance of the given coil by Carey foster bridge.

25

8

To determine the value of two unknown resistances by using a potentiometer and verify the law of combination of resistances in series or parallel.

31

9

To determine the work function of a metal by using a sodium light.

36

10

To determine the ionization potential of mercury.

40

11

To set up half and full wave rectifier and study their waveforms on an oscilloscope.

44

12

To study the characteristics of an RLC series acceptor circuit by plotting a response curve.

52

13

To study the characteristics of an RLC rejecter circuit by plotting a response curve.

57

14

To plot the characteristics curve of a semi conductor diode. Determine the forward and reverse impedances [Resistances].

62

15

To study the static characteristics of a given transistor in common emitter mode.

65

16

To determine the Plank’s constant by using a spectrometer and hydrogen discharge tube.

70

Dated : _______________


5

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 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.

Dated : _______________


6

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.

Dated : _______________


7

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 VS 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

applied voltage V0 is V = V0 [ 1 – e – 1 / CR ]

]

sV

eV

0V

[ log CR 1

t

, ]

sV

eV

0V

[ log CR 2

t

]

s V

eV

eV

0V

[ log CR ] 2

t - 1t [ T Period Flashing

Dated : _______________


8

CIRCUIT DIAGRAM:

OBSERVATIONS: Least count of stop watch = 0 . 01 sec

S. No.

Resistance R

Time for 10 flashes Mean Time

Flashing Period

T = t / 10 1 2 3

Ohms Sec Sec Sec Sec Sec

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

Dated : _______________


9

GRAPH BETWEEN RESISTANCE & FLASHING TIME

Along X – axis One small division = ________ Ohms Along Y – axis One small division = ________ min

Dated : _______________


10

CALCULATIONS: FROM GRAPH

Value of A = R 1 =____________ Ohms

Value of B = R 2 = ____________ Ohms

RESULT: The value of unknown resistances from graph [ using a neon

flash lamp ] are found to be

Value of A = R 1 =____________ Ohms

Value of B = R 2 = ____________ Ohms

The theoretical value of A + B = __________ Ohms The value of A + B from graph = __________ Ohms

The theoretical value of B

1

A

1

= ____ Ohms

The value of A + B from graph B

1

A

1

= ___ Ohms

Teacher’s signature

2R

1

1R

1

R

1

2R

1R

2R

1R

R

R

R = _____________ Ohms

FROM GRAPH

R = B

1

A

1 = ____ Ohms

R = R 1 + R 2

R = + R = _____________ Ohms

FROM GRAPH R = A + B = _____ Ohms

Dated : _______________


11

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.

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

Dated : _______________


12

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.

SR_

HR

SR

HR

gR

] g

R R [

V

gI

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 = Ig + Is _________ [ 1 ]

Is = [ I – Ig ] _________ [ 2 ]

Since Rg and RS are in parallel then by Ohm’s law we have

Dated : _______________


13

Is RS = Ig Rg _________ [ 3 ]

From Equation [ 2 ] and Equation [ 3 ] we get

RS [ I – Ig ] = Ig Rg

]

gI I [

gR

gI

S

R

If the shunt wire has specific resistance and a radius r then it’s required length L is given by

ρ

2r π S L

WORKING FORMULA:

1.

SR_

HR

SR

HR

gR

2.

]g

R H

R[

V

gI

3. ]

gI I[

gR

gI

S

R

3. ρ

2r π S L

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

http://en.wikipedia.org/wiki/Ratio

http://en.wikipedia.org/wiki/Mathematical_constant

Dated : _______________


14

CIRCUIT DIAGRAM:

OBSERVATIONS:

High

Resistance RH

Full Deflection

Half Deflection

Shunt Resistance

RS

SR_

HR

SR

HR

g

R

Ohms Divisions Divisions Ohms Ohms

1. Least count of standard ammeter = ____________ Amp __________Divisions of galvanometer = _________ Amp

One division of galvanometer =

= ________ Amp

2. Least count of converted ammeter = ____________ Amp

VERIFICATION:

S. No.

Standard Ammeter Reading

Reading of the shunted galvanometer

Difference

Galvanometer Divisions

Converted Ammeter

Amperes Divisions Amperes Amperes

1.

2.

3.

4.

5.

6.

Dated : _______________


15

CALCULATIONS:

SR_

HR

SR

HR

gR

_

gR

Ohms

]

gR

HR[

V

gI

p Am

gI

]

gI I[

gR

gI

S

R

Ohms

SR

ρ

2r π S L

cm

2 ][ 142 . 3

L

RESULT: The given galvanometer has been converted in to an

ammeter up to the range [ 0 – 1 ] ampere.


Dated : _______________


16

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.

Dated : _______________


17

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

] g

R X

R [

V

gI

SR_

HR

SR

HR

gR

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

V = Ig [ R X + R g ]

Ig R X + Ig R g = V

Ig R X = V – Ig R g

Dated : _______________


18

gI

gR

gI -V

X

R

gI

gR

gI

gI

V

XR

g

R -

gI

V

X

R

WORKING FORMULA:

1.

SR_

HR

SR

HR

gR

2.

]g

R R [

V

gI

3. g

R -

gI

V

XR

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:

OBSERVATIONS:

Dated : _______________


19

High

Resistance RH

Full Deflection

Half Deflection

Shunt Resistance

RS

SR_

HR

SR

HR

g

R

Ohms Divisions Divisions Ohms Ohms

1. Least count of standard voltmeter = ___________ Amp _________Divisions of galvanometer = __________ Volts

One divisions of galvanometer =

= ________ Volts

2. Least count of converted ammeter = ____________ Volts

VERIFICATION:

S. No.

Standard Voltmeter Reading

Reading of the shunted galvanometer

Difference

Galvanometer Divisions

Converted Voltmeter

Volts Divisions Volts Volts

1.

2.

3.

4.

5.

6.

CALCULATIONS:

SR_

HR

SR

HR

gR

_

gR

Ohms

Dated : _______________


20

]

gR

HR[

V

gI

p Am

gI

g

R -

gI

V

XR

Ohms --

XR --

RESULT:

The given galvanometer has been converted in to a voltmeter up to the range [ 0 – 1 ] volts.


Dated : _______________


21

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.


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.

Dated : _______________


22

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 potential drop is established across a potentiometer by connecting a battery across it. The potential drop per unit length of its wire is measured in terms of EMF of a standard cell. A rheostat is set up as a potential divider. The potential difference for its different setting is measured by a voltmeter and by the potentiometer using the value of potential drop per unit length of the potentiometer wire as already found because of the standard cell and the inherent accuracy of potentiometric voltage measurement , the potential read by potentiometer is the true reading of the potential . This is compared with the reading of the voltmeter and in this way the calibration of voltmeter is checked .

WORKING FORMULA: ]

1L

2

L[

SE

SV

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:

Dated : _______________


23

OBSERVATIONS:

3. Least count of standard voltmeter = _____________ Volts

4. E .M . F of standard cell = E S = _______________ Volts

5. Balancing length when Standard cell is in circuit L1 = __ cm.

S. No

Balancing length when

R 2 is in circuit

L2

Calculated Voltage

]

1L

2

L[

SE

SV

Voltmeter Reading

V

Difference [ VS – V ]

cm volts volts volts

1.

2.

3.

4.

5.

CALCULATIONS: ]

1L

2

L[

SE

SV

]

1L

2

L[

SE

SV

V S = _________ Volts

]

1L

2

L[

SE

SV

V S = _________ Volts

]

1L

2

L[

SE

SV

V S = _________ Volts

]

1L

2

L[

SE

SV

V S = _________ Volts

Dated : _______________


24

RESULT:

The given voltmeter has been calibrated a by using a potentiometer


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.


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.

]

1L

2

L[

SE

SV

V S = _________ Volts

Dated : _______________


25

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 potential drop is established across a potentiometer by connecting a battery across it. The potential drop per unit length of its wire is measured in terms of EMF of a standard cell. A resistance RS an ammeter and A and a rheostat R2 are connected in series with a battery B2 ( as in figure ). Let the current flowing through the circuit as read by the ammeter be I . This current set up a potential drops VS across the standard resistance RS This value of VS is measured by the potentiometer using the value of potential drop per unit length of potentiometer wire. Because of the standard cell and the inherent accuracy of potentiometric voltage measurement, the value of VS is very accurate. The current flowing through the standard resistance RS is thus IS = VS X RS . This is the true value of current flowing through the circuit. It is compared with the reading of the ammeter A and in this way the calibration of ammeter is checked .

WORKING FORMULA: ]

1L

2

L

SR

SE

[ SI

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

Dated : _______________


26

CIRCUIT DIAGRAM:

OBSERVATIONS:

6. Least count of standard ammeter = ___________ Amp

7. E .M . F of standard cell = E S = ______________ Volts

8. Value of standard resistance = RS = ____________ Ohms

9. Balancing length when Standard cell is in circuit L1 ___ cm

S. No

Balancing length when

R S is in circuit L2

Calculated Current

]

1L

2

L

SR

SE

[ SI

Ammeter Reading

I

Difference [ IS – I ]

cms amp amp amp

1.

2.

3.

4.

5.

Dated : _______________


27

CALCULATIONS:

RESULT:

The given ammeter has been calibrated a by using a potentiometer


]

1L

2

L

SR

SE

[ SI

IS = ×

IS = _________ amp

]

1L

2

L

SR

SE

[ SI

IS = ×

IS = _________ amp

]

1L

2

L

SR

SE

[ SI

IS = ×

IS = _________ amp

]

1L

2

L

SR

SE

[ SI

IS = ×

IS = _________ amp

]

1L

2

L

SR

SE

[ SI

IS = ×

IS = _________ amp

]

1L

2

L

SR

SE

[ SI

IS = ×

IS = _________ amp

Dated : _______________


28





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.


resistance in the circuit. Loose plugs in the resistance box. Jockey may not be of sharp edge. Fluctuation of current in the circuit.

Dated : _______________


29

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:

]

1L

2

L[

SE

SV , ]

1

L

2

L

SR

SE

[ SI

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:

Dated : _______________


30

OBSERVATIONS:

1. Least count of standard ammeter = ______ Amp 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

CALCULATIONS:

S. No

Balancing Length when

R S is in circuit

L2

Voltage

VS Voltmeter Reading

V

Current

IS Ammeter Reading

I

Difference

[ VS – V ]

Difference

[ IS – I ]

cm volts volts amps amps volts amps

1.

2.

3.

4.

5.

]

1L

2

L[

SE

SV

VS = ×

VS = _________ volts

]

1L

2

L

SR

SE

[ SI

IS = ×

IS = _________ amp

Dated : _______________


31

RESULT:

The given ammeter and voltmeter have been calibrated a by using a potentiometer


]

1L

2

L[

SE

SV

VS = ×

VS = _________ volts

]

1L

2

L

SR

SE

[ SI

IS = ×

IS = _________ amp

]

1L

2

L[

SE

SV

VS = ×

VS = _________ volts

Dated : _______________


32





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.


resistance in the circuit. Loose plugs in the resistance box . Jockey may not be of sharp edge . Fluctuation of current in the circuit.

Dated : _______________


33

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

] i -[----------- β ρ ]

1L 100 [ Y

α ρ 1

L X

Q

P

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

] ii -[----------- β ρ ]

2L 100 [ X

α ρ 2

L Y

Q

P

From equation [ I ] and equation [ ii ]

β α ρ 100YX

αρ 2

L Y

β ρ 100 Y X

α ρ 1

L X

Q P

P

As the denominator s are equal therefore

X + L 1 + = Y + L 2 +

X – Y = L 1 + – [ L 2 + ]

X – Y = L 1 + – L 2 –

X – Y = [ L 1 – L 2 ]

X = Y + [ L 1 – L 2 ] -------------------- [ iii ]

Dated : _______________


34

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 + [ L 1 – L 2 ]

[ L 1 – L 2 ] = Y ]

2L

1L [

Y ρ

WORKING FORMULA:

]

2L

1L[

Y ρ

, X = Y + [ L 2 – L 1 ]

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:

Dated : _______________


35

OBSERVATIONS: FOR DETERMINATION OF [ The resistance per cm of the wire ] Resistance P = _____ Ohms , Resistance P = ______ Ohms

S. NO

Y

Distance of balancing point from A with shorting strip in

]2

L 1

L[

Y ρ

Mean

L1 L2

Ohm cm cm Ohm / cm Ohm /cm

1.

2.

3.

CIRCUIT DIAGRAM:

OBSERVATIONS:

FOR DETERMINATION OF UNKNOWN LOW RESISTANCE

Resistance P = _____ Ohms , Resistance P = _____ Ohms

S. NO

Y

Distance of balancing point from end A

X = Y + [ L 2 – L 1 ]

L1 L2

Ohm cm cm Ohm

1.

2.

3.

Dated : _______________


36

CALCULATIONS:

]

2L

1L[

Y ρ

ρ

Ohms / cm

]

2L

1L[

Y ρ

ρ

Ohms / cm

]

2L

1L[

Y ρ

ρ

Ohms / cm

MEAN

3

Ohms / cm

X = Y + [ L 2 – L 1 ]

= + [ – ]

= + ×

= +

= ____________ Ohms

X = Y + [ L 2 – L 1 ]

= + [ – ]

= + ×

= +

= ____________ Ohms

Dated : _______________


37

Actual Value = 0 . 3 Ohms

100 ValueActual

ValueCalculated ValueActual Error Of Percentage

100 3 . 0

3 . 0 Error Of Percentage

Percentage of error = ________________ %

RESULT:

The unknown low resistance of the given coil by Carey foster bridge is calculated to be ____________ Ohms.

Percentage of error = ________________ %


X = Y + [ L 2 – L 1 ]

= + [ – ]

= + ×

= +

= ____________ Ohms

MEAN

X

3

= ____________ Ohms

Dated : _______________


38


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.



Dated : _______________


39

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:

1L

]1

L 2

L[ R r

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:

Dated : _______________


40

OBSERVATIONS:

Known Resistance

R

Un known Resistance

r

Balancing length for

R

L1

balancing length for ( R + r )

L2

Un known Resistance

r

1

L

]1

L2

L [ R

Mean Un known Resistance

r

Ohms Ohms Cm Cm Ohms Ohms

r 1

r 2

r 1 + r 2

2r

1

1r

1

CALCULATIONS:

FOR [ r1 ]

1L

]1L

2L[

R r

r = ____________ Ohms

FOR [ r1 ]

1L

]1L

2L[

R r

r = ____________ Ohms

2

r r r Mean

2

r Mean

Mean r = ____________ Ohms

Dated : _______________


41

FOR [ r2 ]

1L

]1L

2L[

R r

r = ____________ Ohms

FOR [ r2 ]

1L

]1L

2L[

R r

r = ____________ Ohms

2

r r r Mean

2

r Mean

Mean r = ____________ Ohms

FOR [ r1 + r2 ]

1L

]1L

2L[

R r

r = ____________ Ohms

FOR [ r1 + r2 ]

1L

]1L

2L[

R r

r = ____________ Ohms

2

r r r Mean

2

r Mean

Mean r = ____________ Ohms

Dated : _______________


42

FOR [ 2

r

1

1r

1

]

1L

]1L

2L[

R r

r = ____________ Ohms

FOR [ 2

r

1

1r

1

]

1L

]1L

2L[

R r

r = ____________ Ohms

2

r r r Mean

2

r Mean

Mean r = ____________ Ohms

Verification of series

combination Put [ r1 & r2 ] from known resistance

[ r1 + r2 ]

e

r

re = ___________ Ohms

Verification of parallel combination Put [ r1 & r2 ]

from known resistance

2 r

1 r

2 r

1 r

e

r

e

r

e

r

re = ___________

Ohms

Dated : _______________


43

RESULT:

Un known resistance r 1 = ____________ Ohms

Un known resistance r 2 = ____________ Ohms

For series combination Observed value [ r 1 + r 2 ] = ____________ Ohms Calculated value [ r 1 + r 2 ] = ____________ Ohms

For parallel combination

Observed value [2

r

1

1r

1 ] = ____________ Ohms

Calculated value [2

r

1

1r

1 ] = ____________ Ohms


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


Dated : _______________


44

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:

e 0

V- λ

c h Φ Function Work ,

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:

Dated : _______________


45

OBSERVATIONS: Least count of voltmeter = ________________________ volts.

Least count of micro ammeter = ____________________ amp. 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 Coulomb.

S.

NO Distance of sodium lamp from Photo cell _____________cm

Voltmeter reading

Volts

Micro ammeter reading Divisions

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

CALCULATIONS: Stopping Potential from graph V 0 = ___________ Volts

e 0

V- λ

c h Φ Function Work

19- 10 6 . 1 - 10 10 5893

8 10 3 34-10 6.625

Work Function = ___________________

Dated : _______________


46

GRAPH BETWEEN

PHOTO CURRENT & APPLIED VOLTAGE

Along X – axis One small division = ________ Volts Along Y – axis One small division = ________ Amp

Dated : _______________


47

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.

Dated : _______________


48

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.

Dated : _______________


49

S.NO

Anode Voltage [ Plate Voltage ]

Volts

Anode Current [ Plate Current ]

Amp 1.

2.

3.

4.

5.

6.

7.

8.

CALCULATIONS: Actual Value = 13 Volts

100 ValueActual


100 13

13 Error Of Percentage

Percentage of error = ________________ % RESULT: The ionization potential of mercury is calculated to be

_______________________ Volts.

Dated : _______________


50

GRAPH BETWEEN

APPLIED VOLTAGE & CURRENT

Along X – axis One small division = _______ Volts Along Y – axis One small division = _______ Amps

Dated : _______________


51

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

Dated : _______________


52

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

R C rf 3 4

1 F . R Factoe Ripple ---------------------- [ 1 ]

300 6- 10 1000 120 3 4

1 F . R Factoe Ripple

3 12 3 4

1 F . R Factoe Ripple

004 . 0 F . R Factoe Ripple

1 2 ) c . d I

rms I

( F . R Factoe Ripple -------------------- [ 2 ]

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 [ 2 ] we get

T

0 2

0I

dt 2 i rms

I and T

0 π

0 I 2

dt i d.c

I

For half wave rectification the values of I r m s and I d .c are given

as under 2

0I

rms I and

π

0I

d.c

I

Dated : _______________


53

FOR HALF WAVE RECTIFICATION Now putting the values of I r m s and I d .c in equation [ 2 ] we get

1 2 )

π

0 I

0 I

( F . R Factoe Ripple 2

1 2 ) 2

( F . R Factoe Ripple


R . F = 1 . 211 FOR HALF WAVE RECTIFICATION Now putting the values of I r m s and I d .c in equation [ 2 ] we get

1 2 )

π

0 I 22

0 I


1 2 ) 2 2



R . F = 0 . 483 CIRCUIT DIAGRAM:

Dated : _______________


54

OBSERVATIONS:

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 Out Put Waveform Filtered

Peak value = F0 = _____ Volts Peak value = F0 = _____ Volts

Dated : _______________


55

d.c out put = F0 = _____ Volts d.c out put = F0 = _____ Volts

FOR FULL WAVE RECTIFIER

SHAPE OF WAVE FORM







In Put Waveform Out Put Waveform Filtered

Peak value = F0 = _____ Volts Peak value = F0 = _____ Volts d.c out put = F0 = _____ Volts d.c out put = F0 = _____ Volts

Dated : _______________


56

GRAPH BETWEEN VOLTAGE & CURRENT


FOR HALF WAVE RECTIFIER

After changing the polarity

Dated : _______________


57

GRAPH BETWEEN VOLTAGE & CURRENT


FOR FULL WAVE RECTIFIER

After changing the polarity

Dated : _______________


58

RESULT : The waveforms of half and full wave rectifier on an

oscilloscope have been studied.

Also studied the effect of smoothing circuit ( filter circuit ) on ripple voltage.


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

Dated : _______________


59

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:

C L π 2

1

rf Frequency Resonant

1f

2f f Δ WidthBand

f

rf

WidthBand

Frequency Resonant factor Q FactorQuality

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:

Dated : _______________


60

OBSERVATIONS:

Resistance R = _______ Ohms.

Inductance L =________ m Henry =________ Henry

Capacitance C = ______ f. = ___________ Farad.

S. NO

Frequency ( f )

Current in the circuit

Log

f

CPS or HZ Amp

01.

02.

03.

04.

05.

06.

07.

08.

09.

10.

CALCULATIONS:

Actual Value =

C L π 2

1

rf

142 . 3 2

1

rf

142 . 3 2

1

rf

1

rf

Hertz

rf

1f

2f f Δ

fΔ

fΔ Hertz

fΔ

rf

factor Q

factor Q

factor Q

Dated : _______________


61

100 ValueActual


100

Error Of Percentage

Percentage of error = ________________ % 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 = _________


Dated : _______________


62

GRAPH BETWEEN

LOG f & CURRENT I

Along X – axis One small division = _______ Hertz Along Y – axis One small division = ________ Amp

Dated : _______________


63

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

Dated : _______________


64

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:

C L π 2

1

rf Frequency Resonant

1f

2f f Δ WidthBand

f

rf

WidthBand

Frequency Resonant factor Q FactorQuality

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:

Dated : _______________


65

OBSERVATIONS: Resistance R = _______ Ohms.

Inductance L =________ m Henry =________ Henry

Capacitance C = ______ f. = ___________ Farad.

S. NO

Frequency ( f )

Current in the circuit

Log

f

CPS or HZ Amp

01.

02.

03.

04.

05.

06.

07.

08.

09.

10.

CALCULATIONS:

Actual Value =

C L π 2

1

rf

142 . 3 2

1

rf

142 . 3 2

1

rf

1

rf

Hertz

rf

1f

2f f Δ

fΔ

fΔ Hertz

fΔ

rf

factor Q

factor Q

factor Q

Dated : _______________


66

100 ValueActual


100

Error Of Percentage

Percentage of error = ________________ % RESULT: The characteristics of an rejecter 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 = _________


Dated : _______________


67

GRAPH BETWEEN

LOG f & CURRENT I

Along X – axis

One small division = _______ Hertz Along Y – axis One small division = ________ Amp

Dated : _______________


68

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

Dated : _______________


69

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 Reverse Bias

Voltage Current Voltage Voltage

Volt Milli ampere Volt Microampere

01.

02.

03.

04.

05.

06.

07.

08.

Dated : _______________


70

GRAPH BETWEEN

VOLTAGE V & CURRENT I

Along X – axis One small division = _______ Volts Along Y – axis One small division = ________ Amp

0

Dated : _______________


71

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. 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

Dated : _______________


72

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:

Dated : _______________


73

OBSERVATIONS:

[ FOR INPUT CHARACTERISTICS ]

KEEPING COLLECTOR TO AMMETER VOLTAGE VCE IS CONCTANT

S. NO

VCE = 0 Volt VCE = 4 Volt VCE = 8 Volt

VBE

IB

VBE

IB

VBE

IB

Volt Amp Volt Amp Volt 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 I B = 60 A

VCE

IC

VCE

IC

VCE

IC

VCE

IC

Volt m A Volt m A Volt m A Volt mA

01.

02.

03.

04.

05.

Dated : _______________


74

GRAPH BETWEEN

Collector To Emitter Voltage V CE &

Collector Current I C Along X – axis One small division = _______ Volts Along Y – axis One small division = ________ Amp

Dated : _______________


75

GRAPH BETWEEN

Base Current I B

& Collector To Emitter Voltage V CE

Along X – axis One small division = _______ Volts Along Y – axis One small division = ________ Amp

Dated : _______________


76

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

Dated : _______________


77

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

31

] ) 2n

1

22

1 (

C

λ 2k 4 e m 2π 2 [ h Constant sPlank'

N

θ Sin d λ

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 = ] [

cm 2.54

lines of no

inch 1 d = ______cm

4. Mass of an electron = m = 9.1072 × 10 – 31 Kg.

5. Charge on an electron = e = 1.6 × 10 – 19 coul.

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

Dated : _______________


78

cm / sec. FOR RED SPECTRAL LINE

S NO

Order Of

Image

Lines Diffraction reading on

Difference Of

Readings

2 = A – B

Angle of diffraction

Wave length

Right

side [ A ]

Left side

[ B ]

deg deg deg deg cm

1. I

D1

2.

I I

D2

FOR BLUE SPECTRAL LINE

S NO

Order Of

Image


Difference Of

Readings

2 = A – B


Wave length

Right

side [ A ]

Left side

[ B ]

deg deg deg deg cm

1. I

D1

2.

I I

D2

FOR VIOLET SPECTRAL LINE

S NO

Order Of

Image


Difference Of

Readings

2 = A – B


Wave length

Right

side [ A ]

Left side

[ B ]

deg deg deg deg cm

1. I

D1

2.

I I

D2

Dated : _______________


79

CALCULATIONS:

Plank’s constant for red spectral line [ n = 3 ]

31

] ) 23

1

22

1 (

Cr



31

] ) 24

1

22

1 (

Cb



31

] ) 25

1

22

1 (

Cv


Actual Value = h = 6.625 × 10 – 34 J – s.

100 ValueActual


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.

Dated : _______________


80

SOURCES OF ERROR : Slit may mot sharp. Spectrometer may not be properly adjusted. Turn table may not be properly adjusted.

4 . b . sc. i i journel

Documents

rlc parallel

neon flash lamp

rlc series acceptor

given coil

response curve

sodium light

thelow resistance ofthe

necessary practical