A 1.6 m tall observer is 45 meters away from a tower. The angle of elevation from his eye to the top of the tower is 30°, then the height of the tower in meters is (Take √3 = 1.732)
Given : CE is the observer of height = 1.6 m and he is at distance of DE = 45 m from tower
To find : Height of tower AD = ?
Solution : By symmetry, BC = DE = 45 m and BD = CE = 1.6 m
In $$\triangle$$ ABC,
=> $$tan(\angle ACB)=\frac{AB}{BC}$$
=> $$tan(30^\circ)=\frac{AB}{45}$$
=> $$\frac{1}{\sqrt{3}}=\frac{AB}{45}$$
=> $$AB=\frac{45}{\sqrt{3}}=15\sqrt{3}$$ m
=> $$AB=15 \times 1.732=25.98$$ m
$$\therefore$$ Height of tower, AD = AB + BD
= $$25.98+1.6 = 27.58$$ m
=> Ans - (C)
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