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Two bodies have their moments of inertia I and 2I respectively about their axis of rotation. If their kinetic energies of rotation are equal, then what is the ratio of their angular velocity.

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प्रश्न

Two bodies have their moments of inertia I and 2I respectively about their axis of rotation. If their kinetic energies of rotation are equal, then what is the ratio of their angular velocity.

योग
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उत्तर

Given:

(K.E.)1 = (K.E.)

∴ `1/2I_1omega_1^2 = 1/2I_2omega_2^2` 

∴ `omega_1/omega_2 = sqrt((I_2)/(I_1))`

= `sqrt((2I)/I)`  ..........(Given: I1 = I, I2 = 2I) 

`omega_1/omega_2 = sqrt2/1`

∴ ω1 : ω2 = `sqrt2` : 1 

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अध्याय 1: Rotational Dynamics - Very Short Answer

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