Question

A10 kg ball is dropped from a height of 10 metres(a) the initial potential energy of the ball ( b). the knietic energy just before it reaches the ground and(c) the speed just before it reaches the gground

Answer 1

Answer:

Given data

Mass of ball (m)= 10kg

Height(h) = 10m

(a) potential energy = mgh

= 10 (kg)× 10 (m/s2) × 10 (m)

=1000 (J)

(b)when the ball reaches the ground the gravitational potential energy changes to kinetic energy

So, kinetic energy gained= 1000(J)

If we neglect the air resistance

(c) We know that Kinetic Energy =and from above data we have kinetic energy as 1000 J and mass of ball (m) as 10kg ,hence on equating for velocity we will get velocity as

V =substituting Kinetic Energy = 1000 J and mass as 10 kg ,we have

Velocity === 14.14 m/s