Question

a 75 kilogram boy initally at rest skis down the slope as shown assuming no frictional loss what will be his kinetic energy at the bottom of the slope

Answer 1

Answer:

The kinetic energy at bottom, K.E = 73500 J

Explanation:

Given data,

The mass of the boy, m = 75 kg

Let the height of the hill be, h = 100 m

The P.E is maximum at the top of the hill. Since the boy is at rest at the top of the hill, his K.E is zero.

When he reaches the bottom, his K.E is maximum and P.E is zero.

According to the law of conservation of energy, K.E at the bottom is equal to the P.E at top.

                          P.E = mgh

                                = 75 x 9.8 x 100

                                = 73500 J

Hence, the kinetic energy at bottom, K.E = 73500 J