Post a New Question

Physics 203 ( College)

posted by .

A disk of radius 12 cm, initially at rest, begins rotating about its axis with a constant angular acceleration of 7.8 rad/s2. What are the following values at t = 4.0 s?

(a) the angular velocity of the disk

(b) the tangential acceleration at and the centripetal acceleration ac of a point at the edge of the disk
at =
ac =

  • Physics 203 ( College) -

    I don't know how to find ac, but I can help you with at and angular velocity of the disk.

    (a) (7.8 rad/s^2)/4.0s = 31.2=angular velocity

    at=7.8*.12=0.936

  • Physics 203 ( College) -

    Tangential acceleration is the instantaneous linear acceleration associated with the particle at distance (r) from the center of rotation.
    thus
    Centripetal Accel= (angular accel)(r)

  • Physics 1301 -

    ac = (omega^2)*(radius)
    = (31.2^2)*(0.12 m)
    = 116.8

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Physics

    A sanding disk with rotational inertia 1.1 x 10^-3 kg*m^2 is attached to an electric drill whose motor delivers a torque of 6 Nm about the central axis of the disk. What are the following values about the central axis at the instant …
  2. physics

    starting from rest, a disk rotates about its central axis with constant angular acceleration. In 4 seconds, it has rotated 50 rad. What was the angualr acceleration during this time?
  3. Physics 1 (Calc Based)

    At t = 0, a wheel rotating about a fixed axis at a constant angular acceleration of –0.40 rad/s^2 has an angular velocity of 1.5 rad/s and an angular position of 2.3 rad. What is the angular position of the wheel at t = 2.0 s?
  4. Physics

    Starting from rest, a disk rotates about its central axis with constant angular acceleration. In 6.00 s, it rotates 28.0 rad. During that time, what are the magnitudes of (a) the angular acceleration and (b) the average angular velocity?
  5. 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?
  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

    1) A circular disk 0.20m in diameter starts from rest and accelerates with constant angular acceleration to an angular acceleration to an angular velocity of 210 rad/s in 10.00s. Find the angular acceleration and the angle which the …
  8. physics

    A disk rotates about its central axis starting from rest and accelerates with constant angular acceleration. At one time it is rotating at 7.8 rad/s; 60 radians later, its angular speed is 19 rad/s. Calculate (a) the angular acceleration …
  9. Physics

    A horizontal disk with a radius of 23 m ro- tates about a vertical axis through its center. The disk starts from rest and has a constant angular acceleration of 5.5 rad/s2. At what time will the radial and tangen- tial components of …
  10. physics

    A disk with mass m = 8.1 kg and radius R = 0.33 m begins at rest and accelerates uniformly for t = 18 s, to a final angular speed of ω = 34 rad/s. What is the angular acceleration of the disk?

More Similar Questions

Post a New Question