The rotational kinetic energies of two flywheels are equal. If the ratio of their moments of inertia is 1 : 9 then the ratio of their angular momenta isA. `5 : 1`B. `1 : 2`C. `2 : 1`D. `1: 4`

The rotational kinetic energies of two flywheels are equal. If the rat

1.	The rotational kinetic energies of two flywheels are equal. If the ratio of their moments of inertia is 1 : 9 then the ratio of their angular momenta isA. `5 : 1`B. `1 : 2`C. `2 : 1`D. `1: 4`
Answer» Correct Answer - C `(1)/(2)I_(1)omega_(1)^(2)=(1)/(2)I_(2)omega_(2)^(2) rArr (omega_(1)^(2))/(omega_(2)^(2))=(I_(2))/(I_(1))` `rArr (omega_(1))/(omega_(2)) = sqrt((I_(2))/(I_(1)))=sqrt((9)/(1))= 3:1` `therefore (L_(1))/(L_(2))=(omega_(2))/(omega_(1))=(1)/(3) rArr L_(1) : L_(2)` `= 1:3`.

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The rotational kinetic energies of two flywheels are equal. If the ratio of their moments of inertia is 1 : 9 then the ratio of their angular momenta isA. `5 : 1`B. `1 : 2`C. `2 : 1`D. `1: 4`

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