# Homework Help: Piano falling down a ramp

1. Sep 15, 2015

### blee2x2

You have a piano that you have just pushed to the top of the 3m long ramp that goes into the truck. The ramp is at a 20-degree angle. You think your friend has a grip on it and she think you do when you all let go. How long do you have before the piano gets to the bottom of the ramp? Assume no friction.

1. The problem statement, all variables and given/known data

How long will it take for the piano at the top of the ramp to get to the bottom of the ramp.
We know the length of the ramp is 3 meter and is angled 20 degrees to the truck. There is no friction.

Can we assume initial velocity is 0m/s?

2. Relevant equations
Xf = Xi + Vi t + .5at^2

3. The attempt at a solution
i am not quit sure if i am using the right equation to solve for time here.

2. Sep 15, 2015

### haruspex

Yes, initial velocity is zero, and that is the right equation to use, but what will the acceleration be?

3. Sep 15, 2015

### billy_joule

EDIT: Posted before seeing post #2

Yes, I would think so.

That equation will work.

The hard part is finding a (acceleration parallel to the ramp). Have you drawn a free body diagram of the piano?