Question

What is the potential energy of a spring that is compressed 0.65 m by a 25 kg block if the spring constant is 95 N/m?

Answer 1

The correct answer to the question is 20.07 J.

CALCULATION:

The mass of the block attached to the spring is given as m = 25 kg.

The force or spring constant of the spring is given as k = 95 N/m.

Due to the block, the spring was compressed to a distance x = 0.65 m.

We are asked to calculate the potential energy of the spring. When the spring is compressed, there will be change in its configuration . Due to this change, the spring will gain elastic potential energy.

The elastic potential energy of the spring is calculated as -

Potential energy P.E =
`(1)/(2)kx^2`

=
`(1)/(2)* 95\ N/m * (0.65m)^2`

= 20.07 Joule [ans]

Hence, the potential energy of the spring is 20.07 J.

Answer 2

PE = 0.5 kx^2 = 0.5 x 95 x (0.65)^2 = 20 J

This formula can be proved with integration.