Answer:
The initial velocity of the ball = 29.7 m/s
Explanations:
The height, H = 45 meters
The acceleration due to gravity, g = -9.8 m/s² (Since the ball is thrown up)
At maximum height, the velocity is 0 m/s. That is, v = 0m/s
We can get the initial velocity using the equation of motion below:
v² = u² + 2gH
0² = u² + 2(-9.8)(45)
0 = u² - 882
u² = 882
u = √882
u = 29.7 m/s
The initial velocity = 29.7 m/s