Question

The angular velocity (in rad/s) of a body rotating at N r.p.m. is

• A. $\pi N/60$
• B. $2\pi N/60$
• C. $\pi N/120$
• D. $\pi N/180$

Answer 1

The correct option is B $2\pi N/60$

Angular velocity is defined as the rate of change of angular displacement with respect to time. It is usually expressed by a Greek letter (omega).
Mathematically, angular velocity is $\omega =d\theta /dt$
If a body is rotating at the rate of N r.p.m. (revolutions per minute), then its angular velocity,

$\omega =\frac{2\pi N}{60}$rad/s