Question

A Blue Ray Disk is spinning with an increasing angular speed. Which of the following statements correctly describes how the centripetal acceleration, a_rad, and the tangential acceleration, a_tan, compare at a point 'A' near the center of the disk, versus point 'B' close to the outer edge of the disk?

A) A and B have the same a_rad, but B has a greater a_tan than A.

B) A and B have the same a_rad and a_tan.

C) B has greater a_rad and a_tan than A.

D) B has a smaller a_rad and a greater a_tan than A.

Answer 1

Ans:(c) B has greater and acceleration than A.

The radial acceleration of point at a distance r from the axis is given by,

Thus the radial accleration is more if the point is more far from the centre. Point A is near the centre and point B is at the outer edge of the disk. So, point B has greater radial acceleration than point A.

The tangential acceleration is given by,

Thus, if a point has more radial acceleration then it has more tangential accleration also. So, point B has more tangential accleration than point A.