NEET2019PhysicsLaws of MotionActual
A block of mass 10   k g is in contact against the inner wall of a hollow cylindrical drum of radius   1   m . The coefficient of friction between the block and the inner wall of the cylinder is 0.1 . The minimum angular velocity needed for the cylinder to keep the block stationary when the cylinder is vertical and rotating about its axis will be g = 10    m   s - 2 ,
Options
- A10   r a d   s - 1
- B10 2 π   r a d   s - 1
- C10    r a d   s - 1
- D10   π    r a d   s - 1
Correct answer
C. 10    r a d   s - 1
Step-by-step solution
N = m ω 2 R f = m g For minimum angular velocity, f = μ N m g = μ · m ω 2 R ω = g μ R = 10 0.1 × 1 = 10 r a d s - 1