Explanation:
The initial kinetic energy is
The final kinetic energy is
The work done W on the car is
The power expended P is
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
More energy is being used in the movement
The product of (mass) x (acceleration) is equal to (force).
So if (force) doesn't change and (mass) changes, then
(acceleration) has to change in the other direction from (mass)
in order to keep their product constant.
If the (forces) on both wagons are equal but one wagon has
double the (mass) of the other, then the more massive wagon
has (1/double) = 1/2 the acceleration of the less massive one.
Answer:
F - w = m a = 2 T - m g net force on man and chair
F = 2 * 368 N = 736 N each rope supports 368 N
a = (736 - 72 * 9.8) / 72 = .422 m/s^2