Question

The rock rolls pff the cliff and falls to the bottom how much kinetic energy. Does the rock possess at the bottom of the cliff ?

Answer 1

A 10kg boulder rests at the edge of a 100m cliff.

Since the rock is at rest , its velocity is zero.

So, initial KE = ½ mu² = ½ m × 0² = 0 Joules.

Now, the rock rolls off the cliff and falls to the bottom.

As per conservation of mechanical energy principle , the whole PE will be converted to KE at the bottom of cliff.

So, KE at bottom of cliff is 100 kJ.