Physics

posted by .

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 -

    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

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Physics

    A 2.0 x 103 kg car is pulled 345 m up a hill that make s an angle of 15° with the horizontal. What is the potential energy of the car at the top of the hill?
  2. Physics

    A 2.0 x 103 kg car is pulled 345 m up a hill that make s an angle of 15° with the horizontal. What is the potential energy of the car at the top of the hill?
  3. Physics

    A 2.0 x 103 kg car is pulled 345 m up a hill that make s an angle of 15° with the horizontal. What is the potential energy of the car at the top of the hill?
  4. Physics

    A hiker throws a ball at an angle of 21.0 degrees above the horizontal from a hill 21.0 m high. The hiker's height is 1.750 m. The magnitudes of the horizontal and vertical components of the velocity are 14.004 m/s and 5.376 m/s, respectively. …
  5. physics

    Determine the work a hiker must do on a 15.8 kg backpack to carry it up a hill of height h = 13.5 m. The hill is not an even slope but rather an irregular curve as in the figure.Determine also the work done by gravity on the backpack
  6. physics

    A hiker climbs a hill 300m high.If she weighs 50kg,calculate the work she does in lifting her body to the top of the hill
  7. Physics

    A 700 kg car is pulled up a hill at a 10 degree hill with a 1500N force acting parallel with the hill, friction can be neglected. What is the work done by the pulling force?
  8. Physics

    A 120kg box is sliding down a hill at a constant speed. The angle of the incline is 32 degrees. Determine the normal force of the hill on the box. Determine the amount of friction on the box.
  9. Science Help

    Drew is walking back up the best hill in the neighborhood 24* grade. He's pulling on the empty 2.1kg sled with a force of 18N at an angle of 55* with the hill. He's walking with a constant velocity, what is the coefficient of friction?
  10. Physics

    A 79.5 kg snowboarder heads down a 28.0° hill that has a height of 62.8 m. If the hill is assumed to be frictionless and there is horizontal wind with a force of 98 N acting against the snowboarder, find the speed of the snowboarder …

More Similar Questions