Question

A high diver dives into a swimming pool. His potential energy at the top is 10,000 J (relative to the surface of the pool). What is his kinetic energy after diving 90% of the distance to the water?

Answer 1

Kinetic energy of diver at 90% of the distance to the water is 9000 J

Step-by-step explanation:

Let d is the distance between the position of the diver and surface of the pool.

Initially, the diver is at rest and only have potential energy which is equal to 10000 J.

As the diver dives towards the pool, its potential energy is converting into kinetic energy due to law of conservation of energy, as total energy of the system remains same.

Energy before diving = Energy during diving

(Potential Energy + Kinetic Energy) = (Kinetic Energy + Potential Energy)

When the diver reaches 90% of the distance to the water, its kinetic energy

is 90% to its initial potential energy, as its initial kinetic is zero,i.e.,

K.E. =
`(90)/(100)*10000`

K.E. = 9000 J