<span>a. The ball accelerates downward with a force of 80.5 N.
This is a rather badly worded question since the answer depends upon whether or not the impact with the gym ceiling was elastic or non-elastic. With an elastic collision, the ball will accelerate downward with it's original force plus the acceleration due to gravity. With a non-elastic collision (the energy in the ball being used to damage the ceiling of the gym), then the initial energy the ball has would be expended while causing damage to the gym ceiling and then the ball would accelerate downward solely due to the force of gravity. In either case, we need to take into consideration the force of gravity. So multiply the mass of the ball by the gravitational acceleration, giving
F = 0.25 kg * 9.8 m/s^2 = 2.45 kg*m/s^2 = 2.45 N
Since the initial force is 78.0 newtons, let's add them
78.0 N + 2.45 N = 80.45 N
and after rounding to 3 figures, gives 80.5 N
So we have a possible answer of 2.45N or 80.5N depending upon if the collision is elastic or not.
And unfortunately, both possible answers are available.
Since no mention of the ceiling being damaged is made in the question, and to be honest a 100% non-elastic collision is highly unlikely, I will assume the collision is elastic, so the answer is "a".</span>
Voltage is how fast the electrons flow. Power is a use of voltage times the volumes of electrons. The higher the voltage the more power you have with the same current.
The statement that can be used to answer this question is:
"If the cylinder is brought higher then, its temperature when brought down becomes higher because a greater amount of potential energy is converted to thermal energy."
The potential energy is converted to thermal energy when the object is released the velocity becomes higher because of the acceleration due to gravity.