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

Options

A. `pi r upsilon`
B. ` 2 pi r upsilon`
C. `pi r^(2) upsilon`
D. `2pi r^(2) upsilon`

Answer

C

Explanation

Area swept out per second = Area swept in one rotation `xx` Number of rotations per unit time `= pi r^(2) upsilon`