Question

In: Physics

A disk rotates about an axis through its center. Point A is located on its rim...

A disk rotates about an axis through its center. Point A is located on its rim and point B is located exactly one fourth of the way from the center toward the rim. What is the ratio of the angular velocity ?A to that of ?B, and the tangential velocity vA to that of vB? the angular velocity ?A to that of ?B the tangential velocity vA to that of vB

Expert Solution

Radius of the disk = R

Angular velocity of the disk =

Point A is on the rim of the disk and point B is one fourth of the distance from the center to the rim.

Distance of point A from the center of the disk = R_A = R

Distance of point B from the center of the disk = R_B = R/4

Angular velocity at point A = _A

Angular velocity at point B = _B

The angular velocity of any point on the disk is equal to the angular velocity of the disk.

_A = _B =

Tangential velocity at point A = V_A

Tangential velocity at point B = V_B

V_A = _AR_A

V_A = R

V_B = _BR_B

V_B = R/4

Ratio of angular velocity at point A to that at point B = 1

Ratio of tangential velocity at point A to that at point B = 4

genius_generous answered 2 years ago

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