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
[tex]s = u t + \dfrac{1}{2}at^2[/tex]
[tex]s = 19.62\times 2 + \dfrac{1}{2}(-9.81)\times 2^2[/tex]
s = 19.62 m
hence, the greatest height at which the ball can reach is 19.62 m.
