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Question
Two discs of the same moment of inertia rotating about their regular axis passing through centre and perpendicular to the plane of the disc with angular velocities ω1 and ω2. They are brought in to contact face to face coinciding with the axis of rotation. The expression for loss of energy during this process is, ______
Options
`1/4I(omega_1 - omega_2)^2`
`I(omega_1 - omega_2)^2`
`1/8I(omega_1 - omega_2)^2`
`1/2I(omega_1 - omega_2)^2`
Solution
Two discs of the same moment of inertia rotating about their regular axis passing through centre and perpendicular to the plane of the disc with angular velocities ω1 and ω2. They are brought in to contact face to face coinciding with the axis of rotation. The expression for loss of energy during this process is, `underline(1/4I(omega_1 - omega_2)^2)`.
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