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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the answer is ampere

the ampere is used to measure electricity. an ampere is a unit of electric current equal. a unit of measure for the flow of current in a circuit. one ampere is the amount of current flow provided when one volt of electrical pressure is applied against one ohm of resistance.

force required to detach it is given by

charges are taken to be fundamental charge

now we have

so above is the minimum distance at which it will detach