NEET2017PhysicsRotational MotionActual
A rope is wound around a hollow cylinder of mass 3 kg and radius 40 cm. What is the angular acceleration of the cylinder if the rope is pulled with a force of 30 N ?
Options
- A25   m   s - 2
- B0.25  rad   s - 2
- C25   rad   s - 2
- D5  m   s - 2
Correct answer
C. 25   rad   s - 2
Step-by-step solution
The torque about centre is τ = I   α , here I is the moment of inertia and α is angular acceleration. The formula of moment of inertia is M R 2 . F × R = M R 2 α 30 × 0.4 = 3 × 0.4 2 α 12 = 3 × 0.16 α 400 = 16 α Thus, angular acceleration is α = 25  rad / s 2