Question

If a building $15\sqrt{3}$ m high casts a shadow of 15 m, then the angleof elevation of the top of the building is ___.

• A. 30°
• B. 45°
• C. 60°
• D. 90°

Answer 1

The correct option is C

60°

Let the angle of elevation be $\theta$.
So,
$\tan \theta =\frac{\text{Length of tower}}{\text{Length of shadow of the tower}}$
$\Rightarrow \tan \theta =\frac{15\sqrt{3}}{15}=\sqrt{3}$
$\Rightarrow \theta ={60}^{\circ }$