A particle performing uniform circular motion gas angular momentum `L`. If its angular frequency is double and its kinetic energy halved, then the new angular momentum is :

Options

A. 2L
B. 4L
C. L/2
D. L/4

Answer

4

Explanation

`(I_(1)omega_(1))/(I_(2)omega_(2))=(L_(1))/(L_(2))`
`omega_(2)=2omega_(1)`
`1/2 I_(2)omega_(2)^(2)=1/2(1/2I_(1)omega_(1)^(2))`
`rArr I_(2)=(I_(1))/8`
`rArr L_(2)=(L_(1))/4`