# Potential Energy Problem

1. Nov 11, 2005

### JOJOKOY

A roller coaster gets over the first hill of height 50.0 meters moving less than 1 meter per second. Then would it stay with the track if it were not mechanically held on to it at the top of the loop the loop. (The top of the loop the loop is 35 meters and it goes 17.1 meters per second at that height). Explain Why or Why Not?

I thought that it would stay with the track anyways because the net force is not great enough.

2. Nov 11, 2005

### Andrew Mason

What do you mean? Not great enough for what? How did you work this out? You can't just guess.

You have to determine the speed of the roller coaster at the top of the loop. How do you do that? (think conservation of energy and assume no losses due to friction or air).

Think of the forces on the roller coaster at the top of the loop. Do a free body diagram showing all the forces. What is the acceleration of the roller coaster at the top if it just makes it around the loop on its own? What provides that acceleration?

AM