Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Current Electricity

Question:

A copper wire of resistance $ 4\Omega$ is melted and redrawn to thrice its original length. The resistance of stretched wire is

Options:

$16\Omega$

$24\Omega$

$36\Omega$

$ 48 \Omega$

Correct Answer:

$36\Omega$

Explanation:

$ R'= \frac{l'2}{l^2} R = 9\times 4\Omega = 36\Omega$