# Work done by gravity on block sliding down incline

1. Oct 13, 2009

### TheNextOne21

Starting from rest, a 5.00 kg block slides 2.50 m down a rough 30.0 incline. The coefficient of kinetic friction betwen the block and incline is .436

i need to find the work done by the force of gravity, work done by the friction force between block and incline and the work done by the normal force.

can anyone help me?

2. Oct 14, 2009

### Gear300

Re: Work

The work done by each force is the dot product between the force and the object's displacement. For gravity, the force is at an angle to the displacement, so you'll need to take that into account. For friction, the force is against the displacement (in the opposite direction of displacement). The normal force is perpendicular to the displacement.

3. Oct 14, 2009

### TheNextOne21

Re: Work

can you elaborate more on the gravity part.

4. Oct 14, 2009

### renaldocoetz

Re: Work

find the vertical (y) components of the force as well as displacement