Two springs of spring constants 1000 N/m and 2000 N/m are stretched with same force. They will have potential energy in the ratio of 

Options

A. `2:1`
B. `2^2 : 1^2`
C. `1:2`
D. `1^2:2^2`

Answer

A

Explanation

Potential energy,
`U = 1/2 kx^2 = 1/2 k (F/k)^2 = (F^2)/(2k)`
As both spring are stretched by same force,
`:. (U_1)/(U_2) = (k_2)/(k_1) = 2000/1000 = 2/1`