The discs are rotating about their axes, normal to the discs and passing through the centres of the discs. Disc D1 has 2 kg mass and 0.2 m radius and initial angular velocity of 50rads−1. Disc D2 has 4 kg mass, 0.1 m radius and initial angular velocity of 200rads−1. The two discs are brought in contact face to face, with their axes of rotation coincident. The final angular velocity (in rad s−1 ) of the system is:
Held on 30 Apr 2013 · Verified 9 Jul 2026.
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A bullet of mass 10 g moving with 400 m/s penetrates a wall and comes to rest. The loss in kinetic energy is:
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Work through every NEET UG Mechanics PYQ, year by year.