Question

What happens to the resistivity of a wire if it is stretched to double its initial length?
1. increse and get double
2. decrease and get half
3. first increase and then decrease
4. remains same

Answer 1

Answer:

4.remains same

Explanation:

resistivity of a material is constant

Answer 2

Answer:

1 increase and get double

Explanation:

R = p*l/A

R1/R2 = l1/l2

l1 = l

l2 = 2l

R1/R2 = L/2L

R1/R2 = 1/2

R2 = 2R1