- 10/√3 mtrs
- 10 × √3 mtrs
- 100 mtrs
- 20 mtrs
Option 2 : 10 × √3 mtrs
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Given,
The angle of elevation of the top of a tower from a point on ground which is 30 m away from the foot of the tower is 30°.
Formula:
tan θ = Perpendicular/Base
Calculation:
Short Trick:
[ alt="F1 M.G 15.6.20 Pallavi D2" src="//storage.googleapis.com/tb-img/production/20/06/F1_M.G_15.6.20_Pallavi_D2.png" style="width: 163px; height: 155px;">
Ratio of AB : BC = 1 : √3
√3 = 30
⇒ 1 unit = 30/√3
⇒ 1 unit = 10 √3
Detailed solution:
AB is a tower and BC = 30 m.
In ΔABC
tan 30° = AB/BC
⇒ 1/√3 = AB/30
⇒ AB = 30/√3
∴ AB = 10 √3 m