Question

A circus artist is climbing a 20m long rope, which is tightly stretched and tied from the top of a vertical pole to the ground. if the angle made by the rope with the ground level is ${30}^{\circ }$,the height of the pole is _________ m.

• A. 20 m
• B. 5 m
• C. 30 m
• D. 10 m

Answer 1

The correct option is D 10 m

Angle of elevation $\theta$ = ${30}^{\circ }$

$\Rightarrow$ Sin$\theta$ = $\frac{perpendicular}{hypotenuse}$

$\Rightarrow$ Sin${30}^{\circ }$ = $\frac{1}{2}$ = $\frac{heightofpole}{20}$

Thus, height of pole = 10 m.