Question

A ball is thrown straight upwards into the air with an initial velocity of 20 m s-1 .How long will it take the ball to reach a height of 15m?How fast will it then be going ? Take g=10ms-2

Answer 1

Answer:

2 sec

Explanation:

u = 20

v = 0

height = 15m

acceleration = 10 m/s

formula = v = u + at

0 = 20 + 10t

-10t = 20

t = $\frac{20}{-10}$

t = -2

= 2 sec