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A wire of length L and 3 identical cells...

A wire of length L and 3 identical cells is now connected in series with a wire of the same material and cross-section but of length by the same amount `Delta T` in the same time t. the value of N is:-

A

4

B

6

C

8

D

9

Text Solution

Verified by Experts

`((3V)^(2))/(R)t=ms DeltaT`
and `((NV)^(2))/(2R)t=2ms Deltat`
`rArr(N^(2))/(4)=9`
`rArr N^(2)=36rArrN=6`
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