question_answer

Two wires are made of the same material and have the same volume. However wire 1 has cross- sectional area A and wire 2 has cross-sectional area 9A. If the length of wire 1 increases by Ax on applying force F, how much force is needed to stretch wire 2 by the same amount?

A) 16F      

B) 25 F

C) 81 F     

D) 64 F