Question

A spring is kept compressed by a small trolley of mass 0.5 kg lying on a smooth horizontal surface as shown. When the trolley is released, it is found to move at a speed of v = 2 ms^-1. What potential energy did the spring possess when compressed?

April 24, 2024

Answer

Mass = 0.5 kg

Velocity = 2 m / s

The potential Energy possessed by the spring is equal to the kinetic energy of moving trolley.

The kinetic energy of trolley = $1\over 2$ × mass × (velocity)²

= $1\over 2$ × 0.5 × 2²

= 0.5 × 2 = 1 J

∴ Potential energy = Kinetic energy = 1.0 J

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