# Homework Help: Work Done By A Constant Force

1. Nov 14, 2007

### alex7298

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

A oerson pushes a 16.0kg shopping cart at a constant velocity for 22.0m at an angle of 29 degrees below the horizontal. A 48.0N frictional force opposes the motion of the cart.
a)what is the magnitude of the force the shopper exerts on the cart.
Determine the work done by b) the pushing force, c) the fricitonal force, and d) the gravitational force

2. Relevant equations

W=(Fcostheta)d
W=Fd

3. The attempt at a solution
well im not sure where to start because using the equation W=(Fcostheta)d leaves you with two variables.
any help would be appreciated

2. Nov 14, 2007

### Supernats

Well, what does that constant velocity tell you about total force?

3. Nov 14, 2007

### alex7298

F=ma
so the net force would be zero, which doesnt make sense becuase the cart is going forward, so wouldnt there have to be a force greater than the one that opposes it?