An 80 kg skateboarder moving at 3 m/s pushes off with her back foot to move faster. if her velocity increases to 5 m/s, what is her change in kinetic energy as a result? j how much work did she perform?

The skateboarder  change in kinetic energy is 160 J and the work done is 160 J

The initial velocity (u) = 3 m/s, final velocity (v) = 5 m/s, mass (m) = 80 kg.

The change in Kinetic energy = (1/2) * m * (v - u)² = 0.5 * 80 * (5 - 3)² = 160 J

The work done = change in kinetic energy = 160 J

Hence the skateboarder  change in kinetic energy is 160 J and the work done is 160 J

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