A tower stands vertically on level ground. From a point P the angle of elevation of the top is 30°. On moving 40 m straight toward the tower to point Q, the angle becomes 60°. Find the height of the tower (in m).

Question

Accepted Answer

20 √3. Let height h, QB = x. tan 60 = h/x => x = h√3. tan 30 = h/x+40 => x + 40 = h √3. So h √3 - h√3 = 40 => h(3-1)√3 = 40 => 2h = 40 √3 => h = 20 √3 m.

A tower stands vertically on level ground.
From a point P the angle of elevation of the top is 30°.
On moving 40 m straight toward the tower to point Q, the angle becomes 60°.
Find the height of the tower (in m).

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 10 Heights and Distances practice

A tower stands vertically on level ground.From a point P the angle of elevation of the top is 30°.On moving 40 m straight toward the tower to point Q, the angle becomes 60°.Find the height of the tower (in m).

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 10 Heights and Distances practice

A tower stands vertically on level ground.
From a point P the angle of elevation of the top is 30°.
On moving 40 m straight toward the tower to point Q, the angle becomes 60°.
Find the height of the tower (in m).