A horizontal disc rotates freely about a vertical axis through its centre. A ring having the same mass and radius as the disc is now gently placed on the disc After same time, the two rotate with a common angular velocity

A horizontal disc rotates freely about a vertical axis through its cen

1.	A horizontal disc rotates freely about a vertical axis through its centre. A ring having the same mass and radius as the disc is now gently placed on the disc After same time, the two rotate with a common angular velocity
Answer» <html><body><p>some friction exists between the <a href="https://interviewquestions.tuteehub.com/tag/disc-955290" style="font-weight:bold;" target="_blank" title="Click to know more about DISC">DISC</a> and the rind <br/>the angular momentum of the disc plus ring is <a href="https://interviewquestions.tuteehub.com/tag/conserved-2539138" style="font-weight:bold;" target="_blank" title="Click to know more about CONSERVED">CONSERVED</a> <br/>the <a href="https://interviewquestions.tuteehub.com/tag/final-461168" style="font-weight:bold;" target="_blank" title="Click to know more about FINAL">FINAL</a> common angular angular velocity is `2//3^("<a href="https://interviewquestions.tuteehub.com/tag/rd-613594" style="font-weight:bold;" target="_blank" title="Click to know more about RD">RD</a>")` of the initial angular velocity of the disc <br/>`2//3^("rd")` of the initial kinetic energy <a href="https://interviewquestions.tuteehub.com/tag/changes-913881" style="font-weight:bold;" target="_blank" title="Click to know more about CHANGES">CHANGES</a> to heat </p>Answer :A::B::D</body></html>