When the roller coaster is at the top of the loop, why doesn’t the person fall off the roller coaster?

What forces are acting on the person when the roller coaster is going round the loop? Is it gravitational force and normal force?

It’s called centripetal force

When the roller coaster is at the top of the loop, the person does not fall off due to the combined effect of a few forces acting on them. These forces include the gravitational force and the normal force.

1. Gravitational force: The force of gravity pulls the person downward toward the Earth. This force is always acting on the person, even during the loop. However, at the top of the loop, the person does not fall because the other forces come into play.

2. Normal force: The normal force is the force exerted by a surface to support the weight of an object resting on it. In this case, the normal force is exerted by the seats of the roller coaster on the person. At the top of the loop, the normal force is directed inward, toward the center of the loop. This force counters the gravitational force and helps keep the person in place.

To understand why the person does not fall off, you can use the concept of centripetal force. Centripetal force is the force that keeps an object moving in a curved path. In this case, the centripetal force is provided by the normal force, as it acts as the inward force required to keep the person moving in a circular path around the loop. The gravitational force is not enough to supply the inward force required for circular motion, and that's where the normal force comes into play.

So, to summarize, the two main forces acting on the person when the roller coaster is going around the loop are the gravitational force and the normal force. The gravitational force pulls the person downward, while the normal force provides the inward force necessary to keep the person on the roller coaster and prevent them from falling off.

well yes sort of but the normal force you are talking about is that giving centripetal acceleration

m v^2/R
at the top of the loop, m g the weight is down
However a normal force in the down direction of m v^2/R is required to keep the person moving in the circular loop.
So as long as m v^2/R is greater than m g, the person does not fall out.
so in the end
v^2/R >/= g
is the condition for not falling out of the roller coaster.