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

## Answer This Question

## Related Questions

- Physics - A hiker throws a ball at an angle of 21.0 degrees above the horizontal...
- Physics - A 79.5 kg snowboarder heads down a 28.0° hill that has a height of 62....
- Physics - A 700 kg car is pulled up a hill at a 10 degree hill with a 1500N ...
- physics - A hiker climbs a hill 300m high.If she weighs 50kg,calculate the work ...
- physics - Determine the work a hiker must do on a 15.8 kg backpack to carry it ...
- Physics - A 2.0 x 103 kg car is pulled 345 m up a hill that make s an angle of ...
- Physics - A 2.0 x 103 kg car is pulled 345 m up a hill that make s an angle of ...
- Physics - A 2.0 x 103 kg car is pulled 345 m up a hill that make s an angle of ...
- Science Help - Drew is walking back up the best hill in the neighborhood 24* ...
- Physics - A 120kg box is sliding down a hill at a constant speed. The angle of ...

More Related Questions