physics

A 290 kg piano slides 4.0 m down a 30° incline and is kept from accelerating by a man who is pushing back on it parallel to the incline (Fig. 6-36). The effective coefficient of kinetic friction is 0.40

  1. 👍 0
  2. 👎 0
  3. 👁 736
  1. (a) Calculate the force exerted by the man.
    (290*9.8*sin 30deg)-(290*9.8cos30deg*0.40)=436.5N
    (b) Calculate the work done by the man on the piano.
    284.2*(-0.40)=-1136.8J
    (c) Calculate the work done by the friction force.
    -3937.6J
    (d) What is the work done by the force of gravity?
    5684 J
    (e) What is the net work done on the piano?
    0J (ZERO J)

    1. 👍 0
    2. 👎 0
  2. 4 sin 30 = 2 meters down
    change in potential energy = work done by gravity = m g h = 290*9.8*2 Joules

    work done by man = -F (4)

    work done by friction = - m g cos 30 (.4)(4)

    since it does not accelerate, the total net work done on it is zero

    - 4 F -290*9.8 (cos 30) (1.6) + 290*9.8*2 = 0
    so
    4 F = 290(9.8) [ 2 - 1.6 cos 30 ]

    1. 👍 0
    2. 👎 0
  3. µk x (m x g) x d x cos 30º

    0.40 x (290 x 9.81) x 4.0 x cos 30º

    hopefully that works

    1. 👍 0
    2. 👎 0
  4. that is the magnitude of the work done by friction
    You did the whole problem with forces, I did it with energy. Same results

    1. 👍 0
    2. 👎 0
  5. ( I did the problem before md8 posted the second time listing the specific questions.)

    1. 👍 0
    2. 👎 0

Respond to this Question

First Name

Your Response

Similar Questions

  1. physics

    A small block is released from rest at the top of a frictionless incline. The distance from the top of the incline to the bottom, measured along the incline, is 3.60 m. The vertical distance from the top of the incline to the

  2. Physics

    A 2.0Kg otter starts from rest at the top of a muddy incline 85 cm long and slides down to the bottom in .50s. What net force acts on the otter along the incline?

  3. physics

    A small block with mass 0.308 kg is sliding down a frictionless ramp that is inclined at an angle of 53.1° above the horizontal. Assume g = 9.80 m/s2. (a) As the object slides down the incline, what is the magnitude of the normal

  4. Physics

    A block slides down a frictionless plane having an inclination of θ = 13.2°. The block starts from rest at the top, and the length of the incline is 1.70 m. -> Find the acceleration of the block. (m/s2 down the incline) -> Find

  1. physics

    A frictionless incline is 5.00 m long (the distance from the top of the incline to the bottom, measured along the incline). The vertical distance from the top of the incline to the bottom is 4.03 m. A small block is released from

  2. physics

    A 380- piano slides 3.8 down a 22 incline and is kept from accelerating by a man who is pushing back on it parallel to the incline. a.Determine the force exerted by the man. b.Determine the work done by the man on the piano.

  3. Physics

    A man pushes on a piano of mass 180 kg so that it slides at a constant velocity of 12.0 cm/s down a ramp that is inclined at 11.0degrees above the horizontal. No appreciable friction is acting on the piano. Calculate the magnitude

  4. physics

    a 330 kg piano slides 3.6 m down a 28 degree incline and is kept from accelerating by a man who is pushing back on it parallel to the incline. the effective coefficient of kinetic froction is 0.4. calculate a) the force exerted by

  1. physics

    A 20.0 kg box slides down a 12.0 m long incline at an angle of 3.0 degrees with the horizontal. A force of 50.0 N is applied to the box to try to pull it up the incline. The applied force makes an angle of 0.00 degrees to the

  2. physics

    A 280 kg piano slides 4.3 m down a 30° incline and is kept from accelerating by a man who is pushing back on it parallel to the incline. The effective coefficient of kinetic friction is 0.40. Calculate: (a) the force exerted by

  3. physic

    A pig slides down a 29° incline in twice the time it would take to slide down a frictionless 29° incline. What is the coefficient of kinetic friction between the pig and the incline?

  4. physics

    A 20.0 kg box slides down a 12.0 m long incline at an angle of 3.0 degrees with the horizontal. A force of 50.0 N is applied to the box to try to pull it up the incline. The applied force makes an angle of 0.00 degrees to the

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