Physics Elasticity Question 102

Question:Two wires of copper having the length in the ratio 4 : 1 and their radii ratio as 1 : 4 are stretched by the same force. The ratio of longitudinal strain in the two will be

Options:

A) 1 : 16

B) 16 : 1

C) 1 : 64

D) 64 : 1

Show Answer

Answer:

Correct Answer: B

Solution:

$ r\propto r\propto \frac{r}{r} $ Ratio of strain =$ \frac{A _{2}}{A _{1}}={{\left( \frac{r _{2}}{r _{1}} \right)}^{2}}={{\left( \frac{4}{1} \right)}^{2}}=\frac{16}{1} $