A vertical tower AT standing on a horizontal plane is observed from two points P and Q in the plane. P and Q are 20m and 70m respectively from the base of the tower(A). The angle of elevation of the top of the tower from P is 2θ and from Q is θ. Find the height of the tower
Answers
Answered by
1
such a big question and you had given only five points I am not interested at all
Answered by
0
Given:
- P and Q are 20m and 70m respectively from the base of the tower(A).
- The angle of elevation of the top of the tower from P is 2θ and from Q is θ.
To find:
The height of the tower.
Solution:
1) Let the height of the tower is h.
2) The ratio for the point P is
- Tan 2Ф = h/20
3) The ratio for the point Q is
- Tan Ф = h/70
- h = 70 TanФ
4) Putting in other equation
- 2TanФ/1-Tan²Ф = 70 TanФ /20
- 2/1-Tan²Ф = 7/2
- 4 = 7 - 7Tan²Ф
- 7tan²Ф = 3
- TanФ =√3/√7
5) Now putting the value of TanФ
- h = 70 √3/√7
- h = 10√21
- h = 10×4.583
- h = 45.83 m.
The height of the tower is 45.83 m.
Similar questions