Question

A wire has a resistance of 10Ω. It is melted and drawn into a wire of half of its length. Calculate the resistance of the new wire. What is the percentage change in its resistance?

Pls Answers UwU

Answer 1

Answer:

75%

Explanation:

Now, since the volume of the wire remains the same even after melting it.

Volume of wire before melting = Volume of wire after melting

Volume = Area * height

R is directly proportional to length.

Let new resistance be R'

R' = R/4

Change in resistance = R - R' => R - R/4 = 3R/4

% of change = 3/4 * 100 = 75%