Question

Angular velocity of hour hand of a watch is

• A. $\frac{\pi}{43200}rads^{-1}$
• B. $\frac{\pi}{30}rads^{-1}$
• C. $\frac{\pi}{21600}rads^{-1}$
• D. $\frac{\pi}{1800}rads^{-1}$

Answer 1

Answer: (C)

Angular velocity = $\frac{angle\, traced }{ time \,taken}$
Time period of hour hand is 12 h . So, $\omega = \frac{2\pi}{12} rad\,h^{-1}$
= $\frac{2\pi}{12 \times 60 \times 60}rad\,s^{-1} = \frac{\pi}{21600}rad\,s^{-1}$