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 ifA. both the length and the radius of the wire we halvedB. both the length and the radius of the wire are doulbedC. The radius of the is doubledD. the length of the wire is doulbed

A constant voltage is applied between the two ends of a uniform metall

1.	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 ifA. both the length and the radius of the wire we halvedB. both the length and the radius of the wire are doulbedC. The radius of the is doubledD. the length of the wire is doulbed
Answer» Correct Answer - B (b) `P = (V^(2))/(R ) = (V^(2) A)/(rho l) prop (r^(2))/(l) [V rarr same]`

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