Question

The angles of elevation and depression of the top and bottom of a lamp post from the top of a 66 m high apartment are 600 and 30° respectively. Find 

(i) The height of the lamp post.

(ii) The difference between height of the lamp post and the apartment

(iii) The distance between the lamp post and the apartment. (√3 = 1.732)

Answer 1

Let AB - Lamp post; CD - Apartment

In the figure

(i) The height of the lamp post is = 66 + x

= 66 + 198

AB = 264 m

(ii) The difference between the height of the lamp post and the apartment is 

BM = AB - AM = 264 - 66

= 198 m (∵ CD = AM)

(iii) The distance between the lamp post and the apartment

y = 66√3

= 114.312 m