Statement
difficulty
A 1 m radius circular disk rotates at constant angular velocity, so that it takes 1.2 s for a full rotation. What is the normal or centripetal acceleration of the external points of its periphery?
Solution
Since the angular velocity is constant and the trajectory of any point is circular we have a uniform circular motion or u.c.m.
Data
R = 1 m
T = 1.2 s
Resolution
If it takes 1.2 s for a full rotation, the disk turns with a period T=1.2 s. From this period, we can calculate the angular velocity of the disk:
Considering the definition of normal or centripetal acceleration, we can calculate its value using the following expression: