# Kinetic and poetenial energy of a roller coaster loop!

1. Dec 19, 2007

### Cate

1. The problem statement, all variables and given/known data
O.k, i'll do my best to explain the problem as I but a picture would probabley be helpful. Basically there's an object of mass m travlleing down an incline. Near the end of the incline it does a loop. The question asks to calculate the normal force(Fn) as a function of ө for 0 ≤ ө ≤ 180 (assume cart is from height h) hint: your answer will depend on m, g, h, r and ө. Check that equation has proper behavior ө= 0 degrees, 90 degrees and 180 degrees.

2. Relevant equations

U= mgh

k=1/2mv^2

3. The attempt at a solution

i understand what's going on it's just putting it into an equation that I find difficult. I am assuming that ө equals zero at the appex before the ascent into the loop. Also, kinetic energy increase as ө increase i think. I'm just no sure if I should do three seperate equations or one if just one then how can it represent all three angles? Any help will be greatly appreciated!

2. Dec 19, 2007

### Cate

After looking at this problem some more I see that the equation kind of looks like the sine function am I on to something?

3. Dec 19, 2007