Question

A small block of mass m = 4.0 kg can slide along the frictionless loop-the-loop. The block is released from rest at point P, at height h = 23R above the bottom of the loop (R is the radius of the loop). Express your answers in the form ngR, where n is the number you will calculate.
a) What is the potential energy when the block is at point P? (Assume the gravitational potential energy of the block Earth system is taken to be zero at the bottom of the loop).
b) What is the potential energy when the block is at point Q (halfway up the loop)?
c) What is the kinetic energy when the block is at the top of the loop?

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