Q.In right-angled triangle ∆ABC,
AC² = AB² + BC² = 3² + 4² = 9 + 16 = 25
So, AC = √25 = 5
In right-angled ∆ABC, if the base is BC, then the height is AB
Again, if the base is AC, then the height is BD
∴ (½) × BC × AB = (½) × AC × BD
⇒ (½) × 4 × 3 = (½) × 5 × BD
⇒ BD = 12⁄5 = 2.4 cm (Answer)
The hour hand of a clock generates a central angle of 360° or \(2\pi\) radians in 12 hours.
\(\therefore\) In 1 hour, the angle formed at the center = \(\frac{2\pi}{12} = \frac{\pi}{6}\) radians.
Since the hand moves in the clockwise direction, the angle will be \(-\frac{\pi}{6}\) radians.