Two particles A and B are moving in uniform circular motion in concentric circles of radii `r_(A)` and `r_(B)` with speed `u_(A)` and `u_(B)` respectively. Their time period of rotation is the same. The ratio of angular speed of a to that of B will be:

Options

A. `1:1`
B. `r_(A):r_(B)`
C. `v_(A):v_(B)`
D. `r_(B):r_(A)`

Answer

A

Explanation

(a): Time period of the circular motion in terms of angular velocity can be written as follows:
Time period `(T) =(2 pi)/(omega)`
`omega`=angular speed
`T_(1)=T_(2)` (given)
`(2pi)/(omega_(1))=(2pi)/(omega_(2))`
`omega_(1)=omega_(2)`
`omega_(1):omega_(2)=1:1`
Hence option (a) is correct.