What does acceleration become if r is cut by 3? a=v^2/r

How do cracks affect the rate of weathering?

How can a cyclist's acceleration change even if its velocity remains constant?

A12-g wad of sticky clay is hurled horizontally at a 100-g wooden block initially at rest on a horizontal surface. the clay sticks to the block. after impact, the block slides 7.5 m before coming to rest. if the coefficient of friction between the block and the surface is 0.65, what was the speed of the clay immediately before the impact?