A particle is kept fixed on a turntable rotating uniformly. As seen from the ground the particle goes in a circle, its speed is `20 cm//s` & acceleration is `20 cm//s^(2)`. The particle is now shifted to a new position to make the radius half of the original value. The new values of the speed & acceleration will be:

Options

A. `10 cm//s, 10cm//s^(2)`
B. `10cm//s,80cm//s^(2)`
C. `40 cm//s,10 cm//s^(2)`
D. `40 cm//s,40 cm//s^(2)`

Answer

A

Explanation

`(v_(2))/(v_(1))=(r_(2))/(r_(1))=(1)/(2)(r_1)/(r_(1))=(1)/(2)`
`v_(2)=(v_(1))/(2)=(20)/(2)=10 cm//s`
`(a_(2))/(a_(1))=(r_(2))/(2r_(1))=(1)/(2)`
`a_(2)=(a_(1))/(2)=(20)/(2)=10 cm//s^(2)`