Question

Two wires are made of the same material and have the same volume. The first wire has cross-sectional area A and the second wire has cross-sectional area 3A. If the length of the first wire is increased by $\Delta l$ on applying a force F, how much force is needed to stretch the second wire by the same amount ?

• A. 9F
• B. 4F
• C. 6F
• D. F

Answer 1

Answer: (A)

9F

Answer 2

The correct option is (A): 9F