Heights and Distances Practice Test 1

Question : 31 of 40

Marks: +1, -0

A man standing at a point P is watching the top of a tower, which makes an angle of elevation of 30°. The man walks some distance towards the tower and then his angle of elevation of the top of the tower is 60°. If the height of the tower is 30 m, then the distance he moves is:

22 m
$22 √3 m$
20 m
$20 √3 m$

Validate

Solution:

From Δ ABC,

30/x=\tan30°=1/√3

x=30√3

......(i)
From Δ ABD,

30/{BD}=\tan 60°=√3

⇒BD=30/√3

......(ii)

y = BC - BD

y=30√3-30/√3=20√3\meter

Go to Question:

Prev Question

Next Question