A telegraph post is bent at a point above the ground. Its

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A telegraph post is bent at a point above the ground. Its top just touches the ground at a distance of 8 √3 metre from its foot and makes an angle of 30° with the horizontal. The height (in metre) of the post is :

Let telegraph pole bend at point A.
BC = 8 √3 metre
In ∆ABC,

tan 30° =	AB
	BC

⇒		1	=	AB
		√3		8√3

⇒ AB =	8√3	= 8 metre
	√3

Again, sin 30° =	AB
	AC

⇒		1	=	8
		AC		2

⇒ AC = 2 × 8 = 16 metre
∴ Height of telegraph–pole
= AB + AC
= 8 + 16 = 24 metre