Question

a copper wire of certain length has a resistance of 10 , what will be its resistance after stretching to double its length ?​

Answer 1

Explanation:

due to doubling the length of wire, the cross sectional area will become half for volume to remain constant . Resistance will increase four times due to doubling the length of wire.

Answer 2

Answer:

$r {}^{2} = 20$

Explanation:

Resistance after stretching Length to Double Will be 20 .

Thank you

Your correct answer is 20.