Question

A football is kicked straight up into the air; it hits the ground 4.0 s later. What was the greatest height reached by the ball? Assume it is kicked from ground level.Express your answer with the appropriate units.

Answer 1

Answer:

the greatest height at which the ball can reach is 19.62 m.

Explanation:

given,

time taken by the ball to reach the ground = 4 s

time at which ball reach at maximum height = 4/2 = 2 s

velocity of the ball at the top most point = 0 m/s

we know,

v = u + a t

0 = u + (-9.81 ) × 2

u = 19.62 m/s

maximum height achieved

$s = u t + \dfrac{1}{2}at^2$

$s = 19.62\times 2 + \dfrac{1}{2}(-9.81)\times 2^2$

s = 19.62 m

hence, the greatest height at which the ball can reach is 19.62 m.