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. 4L
B. 0.5L
C. 2L
D. 0.25L

Answer

D

Explanation

`E_(1)=(1)/(2)I_(1)omega_(1)^(2)=(1)/(2)L_(1)omega_(1)`
`E_(2)=(1)/(2)I_(2)omega_(2)^(2)=(1)/(2)L_(2)omega_(2)`
`therefore (L_(2))/(L_(1))=(E_(2))/(E_(1))xx(omega_(1))/(omega_(2))`
`therefore L_(2)=(L_(1))/(4)=0.25 L`