Answer –
According to the question –
Mass of trolley is 0.5 kg
Velocity is 2 m / s
The potential energy of the compressed spring is totally converted into kinetic energy when it is released.
The kinetic energy of a moving trolley equals the potential energy of a compressed spring.
Using the expression of kinetic energy –
Kinetic energy of trolley = 1 / 2 × mass × (velocity)2
= 1 / 2 × 0.5 × (2)2 = 1 / 2 × 0.5 × 2 × 2
= 1J
Therefore, the potential energy of compressed spring = 1.0J