Home
Class 12
PHYSICS
The moments of inertia of two rotating b...

The moments of inertia of two rotating bodies A and B are `I_(A)` and `I_(B). (I_(A) gt I_(B))` and their angular momenta are equal. Which one has greater `K.E.` ?

A

`K_(1)=K_(2)`

B

`K_(1) lt K_(2)`

C

`K_(1) gt K_(2)`

D

`K_(1)=(1)/(2)K`

Text Solution

Verified by Experts

The correct Answer is:
B

Since the angular momenta are equal
`therefore I_(1)omega_(1)=I_(2)omega_(2)" but "I_(1) gt I_(2)" "therefore omega_(1) lt omega_(2)`
`"K.E. of A "=(1)/(2)I_(1)omega_(1)^(2)=(1)/(2)(I_(1)omega_(1))omega_(1)`
`"K.E. of B"=(1)/(2)(I_(2) omega_(2))omega_(2)" But "I_(1)omega_(1)=I_(2)omega_(2)`
`because omega_(1) lt omega_(2)" "therefore K_(1) lt K_(2)`
Promotional Banner

Topper's Solved these Questions

  • ROTATIONAL MOTION

    MARVEL PUBLICATION|Exercise TEST YOUR GRASP - 3|8 Videos
  • OSCILLATIONS

    MARVEL PUBLICATION|Exercise MCQ|368 Videos
  • SEMICONDUCTORS

    MARVEL PUBLICATION|Exercise MCQs|261 Videos

Similar Questions

Explore conceptually related problems

The moments of inertia of two rotating bodies A and are I_A and I_B(I_A gt I_B) . If their angular momenta are equal then.

The moment of inertia of two freely rotating bodies A and B are l_(A) and l_(B) respectively. l_(A) gt l_(B) and their angular momenta are equal. If K_(A) and K_(B) are their kinetic energies,then

A light and a heavy body have equal momenta. Which one has greater K.E

Two rigid bodies A and B rotate with rotational kinetic energies E_(A) and E_(B) respectively. The moments of inertia of A and B about the axis of rotation are I_(A) and I_(B) respectively. If I_(A) = I_(B)//4 and E_(A)= 100 E_(B), the ratio of angular momentum (L_(A)) of A to the angular momentum (L_(B)) of B is

Two bodies with moment of inertia I_1 and I_2 (I_2 gt I_1) are rotating with same angular momentum. If K_1 and K_2 are their K.E.s, then

Two rigid bodies A and B rotate with angular momenta L_(A) and L_(B) respectively. The moments of inertia of A and B about the axes of rotation are I_(A) and I_(B) respectively. If I_(A)=I_(B)//4 and L_(A)=5L_(B) , then the ratio of rotational kinetic energy K_(A) of A to the rotational kinetic energy K_(B) of B is given by

Two bodies having moments of inertia I_(1) and I_2 (I_(1) gt I_(2)) have same angular momentum. If E_(1) and E_(2) are their rotational kinetic energies,