InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
Circular disc of mass 2 kg and radius 1 m is rotating about an axis perpendicular to its plane and passing through its centre of mass with a rotational kinetic energy of 8 J. The angular momentum is (Js) isA. 8B. 4C. 2D. 1 |
|
Answer» Correct Answer - B Rotational kinetic energy `= (1)/(2)I omega^(2)=8 J` `rArr (1)/(2)xx(1)/(2)mr^(2)omega^(2)=8or (1)/(4)xx2xx(1)^(2)omega^(2)=8` or `omega^(2)=16 or omega=4 "rad s"^(-1)` Angular momentum, `L=Iomega=(1)/(2)mr^(2)omega` `=(1)/(2)xx2xx(1)^(2)xx4=4"J-s"`. |
|