Exams › JEE Main › Physics
A thin uniform rod of length R*sqrt(2) rests inside a hollow uniform sphere of inner radius R, with both ends touching the inner wall. The rod and the sphere have equal mass m. The system is released from rest on a frictionless floor (and the sphere-rod contact is frictionless). By the time the rod swings to a horizontal orientation, how far has the sphere moved horizontally relative to the ground?
- R*sqrt(2)/4
- R*sqrt(2)/2
- R/4
- zero
Correct answer: R*sqrt(2)/4
Solution
Because equal masses share a fixed centre of mass, the sphere shifts by half of the rod's horizontal shift relative to the sphere; that shift equals the perpendicular distance R/sqrt(2) from centre to the chord.
Related JEE Main Physics questions
⚔️ Practice JEE Main Physics free + battle 1v1 →