One particular descent goes from 2100 m to 1600 m. Assuming the work done against friction is 90% of the potential energy change of the cyclist and the cycle, what INCREASE in speed in km/h can a rider attain by the end of the descent?

This problem has been solved! see the answera non-uniform fire escape ladder is 6.0m long whenextended to the icy alley below. it is held at the top by africtionless pivot, and there is neglibible frictional force fromthe icy surface at the bottom. the ladder weighs 250n, and it'scenter of gravity is 2.0m along the ladder from the bottom. amother and child of total weight 750n are on the ladder 1.5m fromthe pivot. the ladder makes an angle θ with the horizontal. find the magnitude and direction ofa) the force exerted by the icy alley on the ladderb) the force exerted by the ladder on the pivotc) do your answers in part a and b depend on the angle?

What are the three ways that an object can accelerate

Explain how the energy of rubber ball is tranforned as it roll down a ramp. give evidence that the energy of the og the ball remains the same at all points on the ramp