NEET2020PhysicsRotational MotionActual
The angular speed of the wheel of a vehicle is increased from, 360   rpm to 1200   rpm in 14   s . Its angular acceleration is,
Options
- A2 π   rad   s - 2
- B28 π   rad   s - 2
- C120 π   rad   s - 2
- D1   rad   s - 2
Correct answer
A. 2 π   rad   s - 2
Step-by-step solution
Given, t = 14   s , ω 0 = 360 60   rps = 12 π   rad   s - 1 , and ω = 1200 60   rps = 40 π rad   s - 1 . Now use the first equation of motion in rotation motion, in terms of angular acceleration and angular velocities, ω = ω 0 + α t ⇒ α = ω - ω 0 t = 28 π 14 = 2 π   rad   s - 2 .