Question

A flywheel rotates at a constant speed of $3000rpm$. The angle described by the shaft in radian in one second is:

• A. $3000\pi$
• B. $100\pi$
• C. $50\pi$
• D. $2\pi$

Answer 1

Answer: (B)

$100\pi$

Given, rotation speed of fly-wheel, $n=3000rpm=\frac{3000}{60}rps=50rps$
Now, the angular velocity $\omega$ is given by:
$\omega =2\pi n$ $=2\pi \left(50\right)=100\pi rad/s$
The angle described by the shaft is:
$\theta =\omega t$
So, for $t=1s$,
$\theta =\omega \times 1=100\pi rad$