JEE — RotorHardQuestion 30658
Question
In a rotor (cylindrical drum rotating at ω), a person stands against the wall (radius R). The person doesn't fall when floor is removed if:
- Aμω²R ≥ gCorrect
- Bμg ≥ ω²R
- Cω²R ≥ g/μ
- Dω ≥ √(g/μR)
Correct answer
μω²R ≥ g
Explanation
Normal force N = mω²R. Friction f = μN = μmω²R ≥ mg. Condition: μω²R ≥ g.