Question

if the wire of the resistance R is melted and recast the half of its length then the new resistance of wire is

Answer 1

Answer:

it decreases by 4 times

Explanation:

R directly proportional to lengthvand inversely proportional to area. when length is halfed then the area of cross section is doubled since the wire is recasted.

$r = \frac{ \frac{l}{2} }{2a} = \frac{l}{4a}$

I am not much sure about it