A post of height 54 m is broken in such a way that its top part is not completely separated but falls to ground and make at an of 30° with the ground. Find the height at which it is broken.

18 m

AC = 54 m

Let, BC = x

A'B = 54 - x

sin 30° = \(\frac{BC}{A'B}\) ⇒ \(\frac{1}{2}\) = \(\frac{x}{54 - x}\)

⇒ 54 - x = 2x

⇒ x = 18 

Therefore, post broke at the height of 18 m