advertisement

BUDS PUBLIC SCHOOL, DUBAI PHYSICS WORKSHEET TOPIC- System of particle and rotational motion Name:________________________ Class:11 Sec:___ Answer these questions: 1. 2. 3. 4. 5. 6. 7. 8. Discuss the motion of centre of mass Obtain the law of conservation of momentum of centre of mass. Define torque. How it related to angular momentum Define angular momentum of a rotating rigid body. Obtain relation between torque and angular acceleration. Define moment of inertia of a body about an axis. Derive expression for kinetic energy of a rotating body. Three bodies a ring, a solid cylinder and a solid sphere roll down an inclined plane without slipping. They start from rest. The radii of the bodies are equal but may have different masses. Which of the bodies reaches the ground with maximum velocity? 9. State and explain parallel axes and perpendicular axes theorems 10. Find the torque of a force 7i+3j-5k about the origin and the force acts on the particle whose position vector is i-j+k 11. Moment of inertia of a thin rod of mass M and length l about an axis through the centre and perpendicular to its length is (Ml2/12). What is its moment of inertia about an axis perpendicular to its length and passing through one of its ends 12. Moment of inertia of a ring of mass M and radius r about any diameter is ½ Mr2. What is its moment of inertia about an any tangent of the ring 13. The angular speed of a motor wheel is increased from 1200 rpm to 3210 rpm in 16 seconds. (a) What is its angular acceleration assuming it to be uniform? (b) How many revolutions does the engine make during this time? 14. A cylinder of mass 5kg and radius 30cm free to rotate about its axis receives an angular momentum impulse of 3kgm2/s initially, followed by similar impulse after every 4 seconds. What is the angular speed of the cylinder 30s after the initial impulse? The cylinder is at rest initially. ----------------********************---------------