Two rotating bodies, A and B of masses, m and 2m with moments of inertia. I _ A and I _ B ( I _ B > I _ A ) have equal kinetic energy of rotation. If, L _ A and L _ B be their angular momenta, respectively, then,

Correct answer: C. L _ B > L _ A E = L ^ 2 2I . ⇒ E _ A = E _ B ⇒ L _ A ^ 2 2 I _ A = L _ B ^ 2 2 I _ B . I _ B > I _ A ⇒ L _ B > L _ A .

NEET 2016

NEET 2016 · Physics · Rotational Motion

Two rotating bodies, A and B of masses, m and 2m with moments of...

Two rotating bodies,

A

and

B

of masses,

m

and

2m

with moments of inertia.

{I}_{A}

and

{I}_{B}

\left({I}_{B} > {I}_{A}\right)

have equal kinetic energy of rotation. If,

{L}_{A}

and

{L}_{B} be their angular momenta, respectively, then,

C. ${L}_{B} > {L}_{A}$

$E = \dfrac{{L}^{2}}{2I}$ .

$⇒ {E}_{A} = {E}_{B}$

$⇒ {L}_{A}^{2}2{I}_{A} = {L}_{B}^{2}2{I}_{B}$ .

${I}_{B} > {I}_{A} ⇒ {L}_{B} > {L}_{A}$ .