Question

If the frequency of the rotating platform is f and the distance of a boy from the centre is r, which is the area swept out per second by line connecting the boy to the centre 

(a) πrf

(b) 2πrf

(c) πr²f

(d) 2πr²f

Answer 1

Correct Option (c) πr²f  

Explanation:

Area swept by line in complete revolution = πr²

If frequency of rotating platform is f per second, then Area swept will be πr²f per second.