MEASUREMENT OF RESISTANCE ( WHEATSTONE’S BRIDGE) gseb std 11 & 12 physics practical.

Wheatstone's bridge

MEASUREMENT OF RESISTANCE

            ( WHEATSTONE’S BRIDGE)

Condition (1) :- MEASUREMENT OF RESISTANCE

AIM :-

You are given a Wheatstone bridge and other necessary instruments. Find the values of the unknown resistance Rx. Exchange the positions of unknown resistance and resistance box in the gaps of Wheatstone bridge and repeat the experiment.

PRINCIPLE :-

It works on the principle of balanced Wheatstone bridge.

Apparatus :-

Wheatstone-bridge (meter-bridge),

2 Volt Battery,

Rheostat,

Galvanometer,          

Jockey,

Key,

Resistance box(1 – 100  W),

Resistance coil.

Precautions

1. Make proper and tight connections.
2. Keep the keys tightly closed in the resistance box.
3. Adjust the value of resistance box so that null point is obtained between 40 cm and 60 cm.
4. Do not slide the jokey continuously over the wire. 

Note :-  Keep high resistance of rheostat in the beginning of each observation so that current is less and the galvanometer is not damaged. After getting approximate position of null point only decrease the resistance of rheostat.

Wheatstone's bridge Appartatus

Wheatstone's bridge Practical

Wheatstone's bridge

Wheatstone's bridge Observation table

Wheatstone Bridge    ( Line Diagram )

(2)  Condition :- Interchange unknown resistance R_x between  P – Q.

Wheatstones bridge appartatus

Wheatstone's bridge practical

Wheatstones bridge observation table

Wheatstosnes bridge conclusion

For more details view Video

MEASUREMENT OF RESISTANCE

            ( WHEATSTONE’S BRIDGE)

LAWS OF COMBINATION OF RESISTORS ( WHEATSTONE’S BRIDGE & POST OFFICE BOX ) Physics practical gseb std 11 & 12

Wheatstone's bridge

 LAWS OF COMBINATION OF RESISTORS

( WHEATSTONE’S BRIDGE & POST OFFICE BOX )

Experiment :- 3.1

AIM :-

You are given a Wheatstone Bridge and other necessary instruments.

Find the values of the unknown resistance Rx and Ry .

Now connect them in series and parallel respectively and measure their resultant resistances and test the laws of series and parallel connections.

PRINCIPLE :-

It works on the  principle of a balanced Wheatstone bridge.

Apparatus :-

Wheatstone-bridge (meter-bridge),

2 Volt Battery,

Rheostat,

Galvanometer, 

Jockey,

Key,

Resistance box(1 – 100  W),

Resistance coil.

Precautions

(1)   Make all connections tight.

(2)    Clean the ends of the connecting wire with a sand paper.

(3)    Plug keys of resistance box should be very tight.

(4)     Adjust the value of R from the resistance box such that null-point is obtained between 40 cm. and 60 cm.

Laws of combination of resistors

Wheatstone's bridge Apparatus

Wheatstone's bridge Line Diagram

Wheatstone's bridge Practical

Wheatstone's bridge Observation table

(2)   Condition :-

Connect unknown resistance R_y between  M – N.

 

Wheatstone's bridge Line diagram

Wheatstone's bridge line diagram

Wheatstone's bridge Practical

Wheatstone's bridge observation table 2

 (3)   Condition :-

Connect unknown resistance Rx & Ry in Series.

 

Wheatstone's bridge series connection condition 3

Wheatstone's bridge condition 3 Line diagram 

wheatstone's bridge practical

Wheatstones bridge observation table condition 3

(4) Condition :-

Connect unknown resistance in Parallel .

Wheatstones bridge parallel connection

Wheatstones bridge parallel connection practical

wheatstones connection conclusion

COMPARISION OF EMF , principle of potentiometer GSEB std 11 & 12 Physics practical

Comparision of emf

COMPARISION OF EMF 

Experiment  6(a)

AIM :-

Two cells EA and EB, a potentiometer and necessary components are given. Connect E_A and E_B one after the other and find the ratio of their emfs.

PRINCIPLE :

It works on the principle of potentiometer.

APPARATUS:

A resistive wire, Laclanche cell, Daniel cell, a main battery, two rheostats, Potentiometer, jokey, key, Galvanometer, Resistance box,

Apparatus for comparision of EMF

Adjust all apparatus as per shown here

Line Diagram fof Comparision of EMF

Line Diagram fof Comparision of EMF

Comparison of EMF Practical

Comparison of EMF Practica

Comparison of EMF Practica

Comparison of EMF Practical Procedure

Calculation table for Comparison of EMF

Experiment  6(b)

AIM :-

Verify the results by joining both the cells in helping and opposing conditions.

APPARATUS :

A resistive wire ( ~ 400  cm length of uniform cross-section fixed on a wooden board, two primary cells ( e.g. Laclanche cell and Daniel cell ), a main battery ( 0 – 12 V ) ( the voltage of this battery must be more than E_A + E_B), two rheostats Rh₁(o - 25W) and Rh₂ ( 0 - 500W)

Apparatus of Comparision of EMF (ii)

PRECAUTIONS

1    First decide from experiment :6(a), which cell has larger emf. Call that cell E_A and the other cell E_B

2      Here, Rh₁ should be having smaller resistance than Rh₂.

3      The value of Rh₁ should be the same while taking observations for EA and E_B.

            For the observation of each set of helping-opposing conditions, the resistance in Rh₁ should not be changed.

Line diagram Comparision of EMF (Helping Connection)

Comparision of EMF Practical

Comparision of EMF Practical

Comparision of EMF Practical

Result :

1  By connecting E_A and E_B separately :  E_A / E_B = ……………

2   By connecting E_A and E_B in helping and opposing conditions : EA / EB = ……..