Question

Kinetic energy of a wheel rotating about its central axis is E. Then kinetic energy of another axis is E. Then kinetic energy of another wheel having twice the moment of inertia and half the angular momentum as that of the first wheel is
A. 8 E
B. 4 E
C. E/8
D. E/4

Answer 1

Correct Answer - C
`I_(2)=2I_(1), L_(2)=(1)/(2)L_(1)`
`(E_(2))/(E_(1))=(L_(2)^(2))/(L_(1)^(2))xx(I_(1))/(I_(2))`
`= (1)/(4)xx(I_(1))/(2I_(1))=(1)/(8)`
`E_(2)=(E_(1))/(8)`