Question

Belly-flop Bernie dives from atop a tall flagpole into a swimming pool below. His potential energy at the top is 15000 J (relative to the surface of the pool). What is his kinetic energy when his potential energy reduces to 1000 J?

Answer 1

At the top, potential energy is 15000 J means there is no kinetic energy at the top.

Therefore,

total energy = potential energy + kinetic energy

total energy = 15000 + 0

total energy = 15000 J

so,

when potential energy is 1000 J, then kinetic energy will be 15000 - 1000 = 14000 J.

This is because total energy needs to be conserved.

Therefore,

kinetic energy = 14000 J