Physics Elasticity Question 131

Question: A fixed volume of iron is drawn into a wire of length L. The extension x produced in this wire by a constant force F is proportional to

[MP PMT 1999]

Options:

A) $ \frac{1}{L^{2}} $

B) $ \frac{1}{L} $

C) $ L^{2} $

D)L

Show Answer

Answer:

Correct Answer: C

Solution:

$ l=\frac{FL}{AY}=\frac{FL^{2}}{(AL)Y}=\frac{FL^{2}}{VY} $ . If volume is fixed then $ l\propto L^{2} $