posted by .

A thin, light string is wrapped around the rim of a 4.00kg solid uniform disk that is 30.0cm in diameter. A person pulls on the string with a constant force of 100N tangent to the disk. Find the linear acceleration of its center of mass. If the disk is replaced by a hollow thin-walled cylinder of the same mass and diameter, what will be the angular acceleration of the disk about its center of mass and what will be the linear acceleration of its center of mass?

  • physics -

    Since the pulled string exerts the only force on the disc (assuming that gravity is ignored here), you can use
    F = m a for the acceleration of the center of mass, in both cases.

    Pulling the string also starts the disk spinning at an acclerating spin rate. Use the relation
    Torque = Force * R = I* alpha
    for the angular rate of acceleration, alpha. I, the moment of inertia, will be different for the solid disc and the thin walled disc, despite the equal masses.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions


    An irregularly shaped plastic plate with uniform thickness and density (mass per unit volume) is to be rotated around an axle that is perpendicular to the plate face and through point O. The rotational inertia of the plate about that …
  2. Physics

    what are the forces acting on a string that is wounded around a uniform disk of Radius R and mass R?
  3. Physics

    A small disk of radius R1 is mounted coaxially with a larger disk of radius R2. The disks are securely fastened to each other and the combination is free to rotate on a fixed axle that is perpendicular to a horizontal frictionless …
  4. Physics

    A 15 kg uniform disk of radius R = 0.25 m has a string wrapped around it, and a m = 3.3 kg weight is hanging on the string. The system of the weight and disk is released from rest. When the 3.3 kg weight is moving with a speed of 2.1 …
  5. physics 101

    A solid uniform disk of mass 21kg and radius 85cm is at rest flat on a frictionless surface. A string is wrapped around the rim of the disk and constant force of 35N is applied to the string, which does not slip on the rim, in the …
  6. physics

    A thin, light horizontal string is wrapped around the rim of a 4.00-kg solid uniform disk that is 30.0 cm in diameter. A box is connected to the right end of the string and moves to the right along the ground horizontally with no friction. …
  7. physics

    A string is wrapped around a uniform disk of mass M = 1.6 kg and radius R = 0.10 m. (Recall that the moment of inertia of a uniform disk is (1/2)MR2.) Attached to the disk are four low-mass rods of radius b = 0.17 m, each with a small …
  8. Physics

    A uniform disk with mass 6 kg and radius 1.8 m is pivoted at its center about a horizontal, frictionless axle that is stationary. The disk is initially at rest, and then a constant force 31.5N is applied to the rim of the disk. The …
  9. Physics

    A uniform disk of radius 0.485 m and unknown mass is constrained to rotate about a perpendicular axis through its center. A ring with same mass as the disk\'s is attached around the disk\'s rim. A tangential force of 0.247 N applied …
  10. physics

    A small disk of radius r is glued onto a large disk of radius R that is mounted on a fixed axle through its center. the combined moment of inertia of the disks is I. A string is wrapped around the edge of the small disk and a box of …

More Similar Questions