Question

A 76kg boulder is rolling horizontally at the top of avertical cliff that is 20.0m above the surface of a lake. The topof the vertical face of a dam is located 100.0m from the foot ofthe cliff, with the top of the dam level with the surface of thewater in the lake. A level plain is 25.0m below the top of thedam.

A) What must the minimum speed of the rock be just as itleaves the cliff so that it will travel to the plain withoutstriking the dam?

B) How far from the foot of the dam does the rock hit theplain