Physics

posted by .

A spinning disk of mass 5.0 kg and radius 0.25m is rotating about an axis through its center at 400 rev/min.
a.) What is the angular velocity of the disk in rad/s?
b.) What is the moment of inertia of the disk?
c.) If it accelerates at a constant rate to 800 rev/min in 8 sec, what is its angular acceleration?
d.) What constant torque is required to produce this acceleration?
e.) When it reaches that speed, what is its kinetic energy?
f.) When it reaches that speed, what is its angular momentum?

  • Physics -

    a) Convert revolutions per minute to radians per second. Surely you can do that.

    b) The moment of inertia of a disc of radius R and mass M is
    I = (1/2)M*R^2

    c) Convert 800 rev/min to
    w = ___ radians/sec, and divide that by 8.0 seconds for the angular acceleration, ____rad/s^2.

    d) Torque = (Moment of inertia)*(angular accleration)

    e) (1/2) I w^2

    f) I*w

    You do the numbers.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Physics

    A woman with a mass of 50kg is standing on the rim of a large disk that is rotating at an angular velocity of .50 rev/s about an axis through its center. The disk has a mass of 110kg and a radius of 4.0m. Calculate the magnitude of …
  2. Physics

    The moment of inertia of an object depends on the shape of the object, location and orientation of the axis of rotation. For a solid disk, when the disk is rotating about an axis that is perpendicular to the disk and passing through …
  3. Physics

    A solid disk rotates in the horizontal plane at an angular velocity of 0.034 rad/s with respect to an axis perpendicular to the disk at its center. The moment of inertia of the disk is 0.11 kg·m2. From above, sand is dropped straight …
  4. Physics

    A solid disk rotates in the horizontal plane at an angular velocity of 0.036 rad/s with respect to an axis perpendicular to the disk at its center. The moment of inertia of the disk is 0.17 kg · m2. From above, sand is dropped straight …
  5. physics

    Two disks are rotating about the same axis. Disk A has a moment of inertia of 3.7 kg · m2 and an angular velocity of +7.3 rad/s. Disk B is rotating with an angular velocity of -9.5 rad/s. The two disks are then linked together without …
  6. physics

    A spinning disk of mass 5.0 kg and radius 0.25m is rotating about an axis through its center at 400 rev/min. a.) What is the angular velocity of the disk in rad/s?
  7. Physics

    Two disks are rotating about the same axis. Disk A has a moment of inertia of 3.8 kg · m2 and an angular velocity of +6.7 rad/s. Disk B is rotating with an angular velocity of -8.9 rad/s. The two disks are then linked together without …
  8. physics

    A solid disk rotates in the horizontal plane at an angular velocity of 0.040 rad/s with respect to an axis perpendicular to the disk at its center. The moment of inertia of the disk is 0.13 kg·m2. From above, sand is dropped straight …
  9. Physics

    Two disks are rotating about the same axis. Disk A has a moment of inertia of 3.1 kg · m2 and an angular velocity of +8.0 rad/s. Disk B is rotating with an angular velocity of -10.2 rad/s. The two disks are then linked together without …
  10. physics

    Two disks are rotating about the same axis. Disk A has a moment of inertia of 3.6 kg · m2 and an angular velocity of +7.9 rad/s. Disk B is rotating with an angular velocity of -10.6 rad/s. The two disks are then linked together without …

More Similar Questions