Question on Work done by horse pulling a wagon.

[Daaniyaal]

Homework Statement

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?

Homework Equations

W=F_net * d

Force of friction= µmg

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

 

[Chestermiller]

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

 

[tiny-tim]

Hi Daaniyaal!

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

work done is force "dot" displacement …

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

 

[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 :)