Question:
The deck of a ship is 10 metre high from water level.Standing on the deck Anu saw the top of a light house at an angle of elevation 60° and bottom at an angle of depression 30° . Find the height of the light house.
Answer:
Let AE is the height of the light house.
Again BD = CE = 10
Then AE = AC + CE
=> AE = AC + 10
Now from triangle BED
tan 30 = BD/DE
=> 1/√3 = 10/DE
=> DE = 10√3
Since BC = DE
So BC = 10√3
Again from triangle ABC,
tan 60 = AC/BC
=> √3 = AC/10√3
=> AC = 10√3*√3
=> AC = 10*3
=> AC = 30
Now AE = AC + 10
=> AE = 30 + 10
=> AE = 40
So height of the light house is 40 m
Not what you are looking for? Go ahead and submit the question, we will get back to you.
