Answer:
The number of revolutions is 10.68 rev/min.
Step-by-step explanation:
Given that,
Radius = 8 m
Suppose, centripetal acceleration equal to the gravity

We need to calculate the velocity
Using formula of centripetal acceleration


Put the value into the formula


We need to calculate the value of

Using formula of velocity


Put the value into the formula


We need to calculate the number of revolutions
Using formula of angular frequency



Put the value into the formula


Using conversion rev/s to rev/min


Hence, The number of revolutions is 10.68 rev/min.