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| 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.
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| Laws of combination of resistors |
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| Wheatstone's bridge Apparatus |
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| Wheatstone's bridge Line Diagram |
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| Wheatstone's bridge Practical |
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| Wheatstone's bridge Observation table |
(2) Condition :-
Connect unknown resistance Ry
between M – N.
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| Wheatstone's bridge Line diagram |
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| Wheatstone's bridge line diagram |
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| Wheatstone's bridge Practical |
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| Wheatstone's bridge observation table 2 |
(3)
Condition :-
Connect unknown resistance Rx &
Ry in Series.
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| Wheatstone's bridge series connection condition 3 |
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| Wheatstone's bridge condition 3 Line diagram |
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| wheatstone's bridge practical |
.PNG) |
| Wheatstones bridge observation table condition 3 |
(4) Condition :-
Connect unknown resistance in Parallel
.
.PNG) |
| Wheatstones bridge parallel connection |
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| Wheatstones bridge parallel connection practical |
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| wheatstones connection conclusion |
