A ball is thrown vertically upwards and leaves the thrower’s hand with a speed of 12m/s.
Calculate the height to which it rises. You may assume that all of the initial kinetic energy
of the ball has been converted into gravitational potential energy when the ball reaches its
highest point. (Take the value of g to be 10N/kg.)

Answer:

9) 7.2 m

Kinetic energy = 0.5mv²
Potential energy = mgh

Since Kinetic energy = Potential energy,

0.5mv² = mgh
0.5 x 144 = 10 x h
h = 72 ÷ 10 = 7.2 m

OR

We can just use a SUVAT equation

v² – u² = 2as

144 – 0 = 2 x 10 x s
s = 144 ÷ (2 x 10) = 7.2 m