Question

(iv) A fuse wire melts at 5 A. It is is desired that the fuse wire of same material melt at 10 A. The new radius of the wire is
(a) 4 times (b) 2 times
(c) $\frac{1}{2}$times (d) $\frac{1}{4}$times

Answer 1

Answer:

Explanation: because when radius increase the melting point increase s due to more volume which takes more time to heat or melt.

Answer 2

Answer:

The new fuse wire should have large radius because current is inversely proportional to the resistance of the conductor and resistance of a conductor decreases on increasing the radius of conductor. Hope it helps!