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State any ‘two’ possible sources of errors in meter-bridge experiment. How can they be minimised?

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#### Solution

**Two possible sources of errors in meter- bridge experiment are:-**

a. Error due to sliding of jockey on the wire:- Due to sliding of the jockey, heat is produced due to friction. Thus the area of wire can be deformed and resistance of the wire may change.

To minimise this error, jockey is tapped on the wire.

b. Error due to heating effect of the cell current:- Heating effect of the wire leads to thermal expansion in the wire. Due to thermal expansion, resistance of wire increases.

To minimise this error, circuit is switched off after every reading.

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