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Two discs of same moment of inertia rotating about their regular axis passing through centre and perpendicular to the plane of disc with angular velocities ω1 and ω2 . They are brought in to

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प्रश्न

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, ______

विकल्प

  • `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`

MCQ
रिक्त स्थान भरें
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उत्तर

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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अध्याय 5: Motion of System of Particles and Rigid Bodies - Evaluation [पृष्ठ २६१]

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सामाचीर कलवी Physics - Volume 1 and 2 [English] Class 11 TN Board
अध्याय 5 Motion of System of Particles and Rigid Bodies
Evaluation | Q I. 9. | पृष्ठ २६१

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Two discs of moments of inertia I1 and I2 about their respective axes (normal to the disc and passing through the centre), and rotating with angular speed ω2 and ω2 are brought into contact face to face with their axes of rotation coincident.

  1. Does the law of conservation of angular momentum apply to the situation? why?
  2. Find the angular speed of the two-disc system.
  3. Calculate the loss in kinetic energy of the system in the process.
  4. Account for this loss.

The magnitude of the torque on a particle of mass 1 kg is 2.5 Nm about the origin. If the force acting on it is 1 N, and the distance of the particle from the origin is 5 m, the angle between the force and the position vector is (in radians) ______.


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