Kinematics Question 551
Question: A fan is making 600 revolutions per minute.If after some time it makes 1200 revolutions per minute, then increase in it’s angular velocity is[BHU 1999]
Options:
A) $ 10\pi rad/\sec $
B)$ 20\pi rad/\sec $
C) $ 40\pi rad/\sec $
D)$ 60\pi rad/\sec $
Show Answer
Answer:
Correct Answer: B
Solution:
Increment in angular velocity $ \omega =2\pi (n _{2}-n _{1}) $
$ \omega =2\pi (1200-600)\frac{rad}{min}=\frac{2\pi \times 600}{60}\frac{rad}{s} $
$ =20\pi \frac{rad}{s} $
