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`

Answer

b

Explanation

Strain `prop` stress `prop (F)/(A)`
Ratio of strain `= (A_(2))/(A_(1)) = ((r_(2))/(r_(1)))^(2) = ((4)/(1))^(2) = (16)/(1)`