Exams › NEET › Physics

A solid homogeneous sphere of mass M and radius R is moving on a rough horizontal surface, partly rolling and partly sliding. During this kind of motion of the sphere

1. (a) total kinetic energy is conserved
2. (b) the angular momentum of the sphere about the point of contact with the plane is conserved
3. (c) only rotational kinetic energy about the centre of mass is conserved
4. (d) angular momentum about the centre of mass is conserved

Correct answer: (d) angular momentum about the centre of mass is conserved

Solution

During rolling and sliding motion, external forces like friction act on the sphere, which can change the angular momentum about the point of contact. However, angular momentum about the center of mass is conserved because no external torque acts about the center of mass.

Related NEET Physics questions

• A uniform rod is resting freely over a smooth horizontal plane. A particle moving horizontally strikes at one end of the rod normally and gets stuck. Then This question has multiple correct options
• The dimensional formula of torque is
• The moment of the force, \( \mathbf{F} = 4\mathbf{i} + 5\mathbf{j} - 6\mathbf{k} \) at \((2, 0, -3)\), about the point \((2, -2, -2)\), is given by
• An object flying in air with velocity (20i + 25j − 12k) suddenly breaks into two pieces whose masses are in the ratio 1 : 5. The smaller mass flies off with a velocity (100i + 35j + 8k). The velocity of the larger piece will be
• At maximum compression, the solid cylinder will stop so loss in kinetic energy of the cylinder equals gain in potential energy of the spring. What is the expression for the energy?
• Two persons of masses 55 kg and 65 kg respectively, are at the opposite ends of a boat. The length of the boat is 3.0 m and weighs 100 kg. The 55 kg man walks up to the 65 kg man and sits with him. If the boat is in still water the centre of mass of the system shifts by:

⚔️ Practice NEET Physics free + battle 1v1 →