Answer:
Gravity
Explanation:
When the ball is falling to the ground, there is only one force- gravity. In some cases, there may be air resistance, but that seems to be neglected here.
Normal force:
Cannot be included. Normal force is only applicable when object is on a surface, and it acts perpendicular to the surface. Since the ball is falling, there is no surface, and therefore no normal force. This question gives you unnecessary information, designed to trick you. Please remember when normal force is applicable.
Friction force:
Also only applicable when object is moving, and is on the table. Friction only applies when there is an applied force. There is no applied force when the ball is falling, so therefore no friction force.
Force of fall:
First of all, what is this? There is nothing called force of fall.
Gravity:
This is the only one that applies. Just draw a vector arrow from the bottom of the ball and label it mg (acceleration due to gravity).
Answer:
Explanation:
TE = KE + PE which is total energy available to a system is equal to its potential energy plus its kinetic energy, and that total energy will remain throughout the entire "trip", whatever it might be. So a is your answer.
The answer is C.energy because it can make light and heat
Answer:
Explanation:
If objects stick together, then a collision is inelastic. When objects don't stick together, If the kinetic energy is the same, then the collision is elastic.
From the time the stone leaves the thrower's hand until it hits the ground, its acceleration is 9.8 m/s^2 downward. Or whatever the acceleration of gravity is on the planet where the toss takes place. It doesn't even have to be tossed vertically. It can be tossed horizontally, or down, or slanty. The answer is the same.