Physics

posted by .

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? (c) What is the instantaneous angular velocity of the disk at the end of the 6.00 s? (d) With the angular acceleration unchanged, through what additional angle (rad) will the disk turn during the next 6.00 s?

  • Physics -

    a) θ = ½ α t² => α = 2 θ / t² = 2 * 20 / 8² = 0.625 rad/s²

    b) ωa = ∆θ / ∆t = 20 / 8 = 2.5 rad/s

    c) ωi = α t = 0.625 * 8 = 5 rad/s

    d) θ = ωo t + ½ α t² = 5 * 6 + ½ 0.625 * 6² = 41.25 rad

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. 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 rev/s. 55 revolutions later, its angular speed is 21 rev/s. (a) Calculate the angular acceleration. …
  2. physics - drwls?

    A disk rotates about its central axis starting from rest and accelerates with constant angular acceleration. At one time it is rotating at 7 rev/s. 55 revolutions later, its angular speed is 21 rev/s. (a) Calculate the angular acceleration. …
  3. 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?
  4. physics

    A 44.3-cm diameter disk rotates with a constant angular acceleration of 2.3 rad/s2. It starts from rest at t = 0, and a line drawn from the center of the disk to a point P on the rim of the disk makes an angle of 57.3° with the positive …
  5. 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 …
  6. Physics 1

    A disk rotates with constant angular acceleration. The initial angular speed of the disk is 2π rad/s. After the disk rotates through 17π radians, the angular speed is 18π rad/s. (a) What is the magnitude of the angular …
  7. Physics

    A wheel starts from rest and rotates about its axis with constant angular acceleration. After 8.7 s have elapsed, it has rotated through an angle of 20 radians. I found that the angular velocity at 8.7 s is 4.60 rad/s. What is the …
  8. Physics

    A wheel starts from rest and rotates about its axis with constant angular acceleration. After 8.7s have elapsed, it has rotated through an angle of 20 radians. What is the angular acceleration of the wheel?
  9. Physics

    A wheel starts from rest and rotates about its axis with constant angular acceleration. After 8.7s have elapsed, it has rotated through an angle of 20 radians. What is the angular acceleration of the wheel?
  10. physics

    Starting from rest, a disk rotates about its central axis with constant angular acceleration. In 4.0 s, it has rotated 30 rad. Assuming that the acceleration does not change, through what additional angle will the disk turn during …

More Similar Questions