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A constant voltage is applied between th...

A constant voltage is applied between the two ends of a uniform metallic wire . Some heat is developed in it. The heat developed is doubled if

A

both the length and the radius of the wire are halved.

B

both the length and the radius of the wire are doubled

C

the radius of the wire is doubled

D

the length of the wire is doubled.

Text Solution

Verified by Experts

The correct Answer is:
D
d. `H = I^2Rt = l/(pir^2)t` .
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