Question

A wire of resistivity ‘r’ is stretched to double its length. How does it affect the
(a) resistance (b) resistivity?

Answer 1

Answer:

Resistance also gets doubled. R = rho×L/ A

R is directly proportional to length so when L doubles r also doubles.

resistivity is inversely proportional to length . so when length is doubled resistivity decreases

Answer 2

Answer:

R= resistivity×L/A

R=resistivity×2L/A

a) resistance will become twice the given resistance.

b) resistivity will become half of given resistance.

Explanation:

hope you understand.