Question

A wire of resistance 16 ohm is melted and drawn into a wire of half its original length. Calculate the resistance of the new wire and the percentage change in resistance?

Answer 1

let the initial length of d wire be "l "

n d area of cross section be "A"

it's resistance = 16ohm (given)

so 16 = l/ A------(1)

after melting

length of wire =l/2

area of cross = 2A

let d resistance offered be R'

so, R'= l/2 / 2A
R' = l/4A
R'= 1/4(l/A)
R'=1/4 (16) [ by eqn 1]
R'=4 ohm....
Resistance of d new wire = 4ohm

Answer 2

Answer:

Explanation:

A wire has resistance of 16 Ω . It is melted and drawn into a wire of half its length .

Calculate the resistance of the new wire . What is the percentage change in its resistance ?

Pls show full calculation