the shadow of a tower standing on a level ground is found to be 30m longer when the sun's altitude is 30 degrees then when it is 60 degree find the height of the tower
Answers
Answer: 15√3m
Step-by-step explanation:
See attachment!!!
Given:
Angles of elevation=60° and 30°
To find:
The height of the tower
Solution:
The height of the tower is 15m.
We can find the height by following the given steps-
Let us assume that the height of the tower be H and the length of the shadow from the foot of the tower to the point from where the angle of elevation is 60° is D.
We are given that the length of shadow increases by 30m when the angle of elevation decreases to 30°.
So, the length of the shadow from the foot of the tower to the point from where the angle of elevation is 30° is (D+30)m.
We will find the height by using the concept of trigonometry.
When the angle of elevation is 60°, the height/length of shadow=tan 60°.
H/D=
H=D
When the angle of elevation is 30°, the height/length of shadow=tan 30°.
H/(D+30)=1/
H=D+30
On substituting the value of H,
D×=D+30
3D=D+30
3D-D=30
2D=30
D=15m
So, the value of H=D=15m.
Therefore, the height of the tower is 15m.