Question

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 ? only answer no follow me or.......

Answer 1

Answer:

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

16 = I/A

length of wire= I/2

area of cross=2A

let D resistance offered be R

R=1/2/2A

=1/4A

=1/4(16)

=4 ohm