NEET2016PhysicsRotational MotionActual
A uniform circular disc of radius 50  cm at rest is free to rotate about an axis which is perpendicular to its plane and passes through its centre. It is subjected to a torque which produces a constant angular acceleration of 2.0   r a d   s - 2 . Its net acceleration in m  s - 2 at the end of 2.0 s is approximately:
Options
- A8.0
- B7.0
- C6.0
- D3.0
Correct answer
A. 8.0
Step-by-step solution
At the end of 2 sec, w = w 0 + α t w = 0 + 2 2 = 4 rad/sec Particle acceleration towards the center is = a c = r w 2 a c = 1 2 4 2 = 8 m/s 2 Tangential acceleration a t = α ⋅ R = 1 m/s 2 a net = a c 2 + a t 2 = 8 2 + 1 2 = 65 ≈ 8 (approximately)