Given,
Mass of the ball (m) = 1.50 x 10³ kg = 1500 kg
Height raised = Displacement of the ball (D) = 40.0 m
Time taken (t) = 20 seconds
Power = Work done(W) ÷ time taken (t)
Work done (W) = Force (F) x Displacement (D)
Force (F) = Mass (m) x Acceleration due to gravity (g)
Acceleration due to gravity for earth (g) = 9.81 m/s²
Therefore,
Force (F) = 1500 x 9.8 = 14715 N
Work done = Force x Displacement = 14715 x 40 = 588600 Joules
Now,
Power = Work done ÷ time taken = 588600 ÷ 20 = 29430 Watts