Question

What fraction of a clockwise revolution does the hour hand of a clock turn through, when it goes from,

$\left(\mathrm{a}\right)3\mathrm{to}9$

Answer 1

Find the fraction of a clockwise revolution

As we know,

In watch, hour hand travel $12$ hours to complete one revolution.

When hour hand goes from $3\mathrm{to}9$. Then, hour hand travels total $6$ hours.

$$\begin{gathered} \because 12\mathrm{hours}=1\mathrm{Revolution} \\ \therefore 6\mathrm{hours}=\frac{1}{12}\times 6 \\ =\frac{1}{2}\mathrm{Revolution} \end{gathered}$$

Hence, when hour hand goes from $3\mathrm{to}9$. Then, it is equivalent to $\frac{1}{2}$ of a revolution.