A stone is thrown vertically upwards with a speed of 20 m/s. How high will go before it begins to fall? (g = 9.8 m/s2)
Initial velocity, u = 20m/s
Final velocity, v = 0
Acceleration due to gravity, g = - 9.8m/s2
Height, h=?
Using relation, for a freely falling body:
v2 = u2 + 2gh
(0)2 = (20)2 + 2 x (-9.8) x h
0-400 = -19.6 h
h= 400/19.6 = 20.4 m