Friday, October 27, 2023

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 Ry 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