Question

A boy in a wheelchair (total mass, 46.0kg) wins a race with a skateboarder. He has a speed of 1.33m/s at the crest of a slope 2.24m high and 13.2m long. At the bottom of the slope, his speed is 6.35m/s. If air resistance and rolling resistance can be modeled as a constant frictional force of 42.1N, calculate the work he did in pushing forward on his wheels during the downhill ride.
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