Question

Question 5 (d)

Find the number of right angles turned through by the hour hand of a clock when it goes from
10 to 1

Answer 1

A complete revolution of the hour hand covers 12 hours or four right angles i.e ${360}^{\circ }$.Which means 1 hour = ${30}^{\circ }$.
When the hour hand goes from 10 to 1, the time difference = 3 hours i.e one-fourth of 12 hours.
$\Rightarrow$ $\frac{1}{4}$ of ${360}^{\circ }$
$\Rightarrow$ ${90}^{\circ }$
= One right angle.