A closed system . I'm assuming you talking about a reversable reaction
A single pulley changes the direction of the effort, but it has
no mechanical advantage. The output force is the same as
the input force, so we'd say that the mechanical advantage is 1.
If there are two pulleys, with the rope going up and down and
around between them several times on its way from the effort
to the load, an arrangement that I think is called 'block and tackle',
then the mechanical advantage turns out to be the number of
strands of rope that are supporting the load.
Answer: No
Explanation: Simply Power’s Si base unit is kgm^2s^-3 but work done‘s Si base unit is kgm^2s^-2.
So this itself proves that they arent the same!
Vox = ?
Voy = 0 m/s
g = 9.8 m/s
s = 61.7 m
h = 42.4 m
(1)-----------------------------------...
To find the time taken for the ball to travel to the bottom:
For constant acceleration,
s = Voy*t + 0.5*g*t^2
42.4 = 0 + 0.5(9.8)*t^2
t^2 = 42.4 / 4.9
t^2 = 8.6531
t = 2.9417s
(2)-----------------------------------...
For the intial velocity of the horizontal component (Vox) of the ball:
s = Vox*t + 0.5*a*t^2
There is no force acting on the horizontal component, so there is no acceleration.
s = Vox*t
61.7 = 2.9417*Vox
Vox = 181.5029 m/s
(3)-----------------------------------...
Since there is no acceleration acting on the horizontal component, x, it remains constant throughout.
Hence, it is still 181.5029 m/s.
For the final velocity of the vertical component (Vfy) of the ball:
(Vfy)^2 = (Voy)^2 + 2*a*h
Acceleration in this case is the force of gravity.
(Vfy)^2 = 0 + 2*(9.8)*(42.4)
(Vfy)^2 = 831.04
Vfy = 28.8278 m/s
I've clearly explained every step. Hope that answers your question! =D