Physics

You want to use a rope to pull a 12-kg box of books up a plane inclined 30∘ above the horizontal. The coefficient of kinetic friction is 0.29. The rope pulls parallel to the incline.

What force do you need to exert on the rope if you want to pull the box with a constant acceleration of 0.50 m/s2 up the plane?

I found that the force you would need to use at constant speed would be 88.3 N

  1. 👍
  2. 👎
  3. 👁
  1. m*g = 12kg * 9.8N/kg = 117.6 N. = Wt. of
    box.

    Fp = 117.6*Sin30 = 58.8 N. = Force
    parallel to the incline.

    Fn = 117.6*Cos30 = 101.8 N. = Normal =
    Force perpendicular to the incline.

    Fk = u*Fn = 0.29 * 101.8 = 29.53 N. =
    Force of kinetic friction.

    Fex-Fp-Fk = m*a
    Fex-58.8-29.53 = 12 * 0.50
    Fex - 88.33 = 6
    Fex = 94.3 N = Force exerted.

    Note: The box is to be pulled with constant acceleration NOT constant velocity.

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Physics

    A rope is used o pull a metal box 15.0m across the floor. The rope is held at an angle of 46.0 degrees with the floor and a force of 628N is used. How much work does the force of the rope do?

  2. physics

    a girl is using a rope to pull a box that weighs 300N across a level surface with constant velocity. the rope makes an angle of 30 degree above the horizontal and the tension in the rope is 100N. What is the normal force of the

  3. Physics

    1.A student moves a box of books down the hall by pulling on a rope attached to the box. The student pulls with a force of 181 N at an angle of 20.8◦ above the horizontal. The box has a mass of 40.3 kg, and μk between the box

  4. physics

    A student pulls on a rope attached to a box of books and moves the box down the hall. The student pulls with a force of 182N at an angle of 25° above the horizontal. The box has a mass of 35kg and &mu k between the box and the

  1. physics

    a mule uses a rope to pull a box that weighs 3.0x10^2N across a level surface with a constant velocity. the rope makes an angle of 30.0 degrees above the horizontal and the tension in the rope is 1.0x10^2N. what is the normal

  2. Physics

    A student decides to move a box of books into her dormitory room by pulling on a rope attached to the box. She pulls with a force of 130 N at an angle of 30.0° above the horizontal. The box has a mass of 24.0 kg, and the

  3. Physics

    A rope is tied to a box and used to pull the box 1.7 m along a horizontal floor. The rope makes an angle of 30∘ with the horizontal and has a tension of 5 N. The opposing friction force between the box and the floor is 1 N. Part

  4. physics

    Boxes A and B are connected to each end of a light vertical rope. A constant upward force F = 80.0 N is applied to box A. Starting from rest, box B descends 12.0 m in 4.00 s. The tension in the rope connecting the two boxes is

  1. Physics

    At the beginning of a new school term, a student moves a box of books by attaching a rope to the box and pulling with a force of F = 84.4 N at an angle of 64degrees. The acceleration of gravity is 9.8 m/s/s. The box of books has a

  2. Physics

    A horizontal rope is tied to a 45.0kg box on frictionless ice. What is the tension in the rope if: A) The box is at rest? B) The box moves at a steady vx = 4.40m/s ? C) The box vx = 4.40m/s and ax = 4.60m/s2 ?

  3. Physics

    A 20 kg box approaches the foot of a 30 degree inclined plane with a speed of 10 m/s. the coefficient of friction between the box and the inclined plane is 0.2. (a) How far up the inclined plane will the box go? (b) If the box

  4. physics

    A student moves a box of books down the hall by pulling on a rope attached to the box. The student pulls with a force of 173 N at an angle of 27.5 above the horizontal. The box has a mass of 27 kg, and μk between the box and the

You can view more similar questions or ask a new question.