A vertical pole of height H stands on the ground. From a point P on the ground, the angle of elevationof the top of the pole is 60°. From a different point Q, located 10 meters away from point P (directly along the line extending from the base of the pole), the angle of elevation to the top of the pole is 30°. What is the height of the pole?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 5 m.

Let distance BP = x, then distance BQ = x + 10
At P:
⇒ tan60° =
⇒ √3 =
⇒ H = x√3................1
At Q:
⇒ tan30° =
⇒
⇒ H = ...............2
Compare eq 1 and 2
⇒ x√3 =
⇒ 3x = x + 10
⇒ 2x = 10
⇒ x = 5
Now height:
⇒ H = x√3 = 5√3 m