Posted by **John** on Monday, March 14, 2011 at 5:41pm.

If a box is being pulled up a hill at an angle to find work, its W=Fdcos(angle)

If a hiker is walking up a hill, the work done is W=mgh right?

When do you know when you can use what formula?

- Physics -
**bobpursley**, Monday, March 14, 2011 at 7:33pm
No, that is not exactly the formula.

What is better is force*distance*cosTheta, where Theta is the angle between force and distance.

In the case of the hiker, mg is downward, but the force is in the opposite direction, h is vertical, so the angle between force and distance is zero, so it ends up mgh (coszero)=mgh

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