Q126 / 150 · MHT CET 2009 · Physics
The ratio of angular speeds of minute hand and hour hand of a watch is
- A$1: 12$
- B$6: 1$
- Correct answerC$12: 1$
- D$1: 6$
Solution
$\omega_{\min }=\frac{2 \pi}{60} \frac{\mathrm{rad}}{\min }$
and $\omega_{\mathrm{hr}}=\frac{2 \pi}{12 \times 60} \frac{\mathrm{rad}}{\mathrm{min}}$
$$
\begin{aligned}
\therefore \frac{\omega_{\min }}{\omega_{\mathrm{hr}}} &=\frac{2 \pi / 60}{2 \pi / 12 \times 60} \\
&=\frac{12}{1}
\end{aligned}
$$
Hence, the correct answer is option: 'C'.