# Homework Help: Question on Work done by horse pulling a wagon.

1. Oct 28, 2013

### Daaniyaal

1. The problem statement, all variables and given/known data
How much work did a horse do that pulled a 200-kg wagon 50 km without acceleration along a level road if the effective coefficient of friction was 0.060?

2. Relevant equations
W=Fnet * d

Force of friction= µmg

3. The attempt at a solution

W=200*9.8-(200*9.8*0.060)*50,000
=92120000

Correct answer is supposed to be 5.9*106

2. Oct 28, 2013

### Staff: Mentor

Your equation doesn't make sense. Where did that first term come from? The correct answer should just be the second term with a plus sign. If you recalculate the expression you gave, you will find that you evaluated it incorrectly.

Chet

3. Oct 28, 2013

### tiny-tim

Hi Daaniyaal!
work done is force "dot" displacement

what is the dot product of the vertical weight with the horizontal displacement?

4. Oct 28, 2013

### Daaniyaal

I guess I unnecessarily put in the force needed to move the wagon without friction opposing the movement. Oopsies

I feel embarrassed >.>

Also, thank you :)