Question
If the angle of elevation of a cloud from a point 200 m above a lake is 30∘ and the angle of depression of the reflection of the cloud in the lake from the same point is 60∘, then the height of the cloud above the lake is:
Answer: Option A
:
A
Was this answer helpful ?
:
A
In â–³ ABC',
tan60∘=x+400AB
       √3=x+400AB
       AB=x+400√3___(i)
In â–³ ABC,
tan30∘=xAB
1√3=xAB
AB=x√3 _______(ii)
Plugging the value of AB from equation (ii) in equation (i), we get
⇒x√3=x+400√3
⇒   3x=x+400
⇒     x=200 m
Hence, the height of the cloud above the lake is
200 + 200 = 400 m
Was this answer helpful ?
Submit Solution