At E the potential energy is maximum/highest. The potential energy decreases as it goes down and increases as it goes up. so if the pendulum swinged from E to A, potential energy would decrease till C and increase till A.
The correct answer is
<span>c the friction force from the road
In fact, the friction force between the road and the tires of the car acts as centripetal force, keeping the car in circular motion.</span>
The answer is position 3, because it is at its lowest point.
Potential Energy is “stored energy.” It is energy that is ready to be converted or released as another type of energy. We most often think of potential energy as gravitational potential energy. When objects are higher up, they are ready to fall back down. When you stretch an object and it has a tendency to return to its original shape, it is said to have elastic potential energy. Chemical potential energy is the stored energy in a substance’s chemical structure that can be released in a chemical reaction or as heat.
Your answer for part a is correct. Using Newton's 3rd Law, the force on the rocket by the exhaust leaving the rocket is the same magnitude (opposite direction) as the downward force applied to the exhaust.
In part b the net force is the upward force from the exhaust thrust minus the downward force of gravity:

Then using the Second Law, we get for part c:

The force and acceleration are in the upward direction