A uniform solid sphere is rigidly attached to a small point mass by a light rod
PHYSICS · Single correct · CBSE · Physics · System of Particles and Rotational Motion · System of Particles and Rotational Motion
Problem
A uniform solid sphere is rigidly attached to a small point mass by a light rod, forming a “lollipop” assembly. The assembly slides without rotation on frictionless ice until it begins to roll without slipping up a gentle incline.
To predict how high the center of mass will rise before coming to rest, which modeling choice and justification is most appropriate?
(a) Treat the sphere as a rigid system and the point mass as a particle, because only the sphere can rotate while the point mass cannot store rotational energy.
(b) Treat the entire assembly as a single particle, since only the center-of-mass kinetic energy will convert to gravitational potential energy.
(c) Treat the assembly as a rigid system for energy considerations but as a single particle for center-of-mass translation, because both translational and rotational kinetic energies convert to potential energy.
(d) Treat the sphere and point mass as two independent particles, because the light connecting rod does not affect how their separate translational energies convert to gravitational potential energy.