# Falling balls, colliding

1. Jul 9, 2009

### rahmatkat

Hi there, can anyone help me with this problem, I'll be grateful to received your help.

It was like this, we were doing an experiment on collision and this is how it goes;

We place a ramp on table and a sheet of paper at the bottom of the table but close to the edge. Then we put two balls, one at the top of the ramp ready tobe release and one at the end of the ramp (stationary).Then the ball at the top of the ramp was release and hit the ball at the bottom, the diagram which I have drawn shows the direction of the two balls and a resultant.

View attachment Collision.doc
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

The Question is that, we have to explain if a velocity for this experiment is conserved or not and if momentum of collision is also conserved or not?

Last edited: Jul 9, 2009
2. Jul 9, 2009

### RoyalCat

Re: Collision

I don't quite know how the rest of the experiment goes, but from what I can see, you're supposed to determine whether momentum is conserved, and whether mechanical energy is conserved (What the instructions called velocity).

Look to see if the following two conditions hold true, by calculating the left and ride side of each equation:
$$P_i=P_f$$
$$E_{k_i}=E_{k_f}$$

Remember that the kinetic energy of the impacting ball right before the collision is equal to its initial potential energy (Assuming conservation of energy, you'd have to neglect the effect of friction to achieve this).

Oh, and don't forget that rolling motion is another form of kinetic energy, so you'd have to take that into account as well.

3. Jul 9, 2009

### rahmatkat

Re: Collision

So I have to find out the kinectic energy of the two ball's as well, I think that were i got everything wrong 'cause I was only trying to find the velocity of the balls. Thank for the help.