# Homework Help: Pushing Cart Down a Ramp

1. Sep 12, 2008

### FuzzyDunlop

1. The problem statement, all variables and given/known data
A professor has to haul a cart down a ramp. The ramp has an angle of about 10 degrees and is about 5 meters long. His initial speed at the top of the ramp is 6 m/s, and the cart has a mass of about 95 kg. How hard does he have to pull on the cart so that at the bottom of the ramp, its speed does not exceed 7 m/s? Neglecting friction, what is the magnitude of the minimum force he has to exert on the cart?

Initial Velocity: 6m/s
Final Velocity: 7m/s
Mass: 95kg
Distance: 5m
Angle: 10

2. Relevant equations

Vf^2=Vi^2 +2ax
F=ma

3. The attempt at a solution

Well first I found the acceleration of the cart.

49=36 +2a(5)
a=1.3

Then I thought that the net force would be
F=mgsin10 + ma

so

F= 95*9.8*sin(10) + 95*1.3 = 285 N

But Im still getting it wrong. Did I make a mistake someplace?

2. Sep 12, 2008

### FuzzyDunlop

Ohh nevermind I got it. I was right, dumb mistake.