A circus artist is climbing a 20 m long rope, which is tightly stretched and tied from the top of a vertical pole to the ground. Find the height of the pole, if the angle made by the rope with the ground level is 30º (see figure).

In \( ∆ \ ABC \) , \( \frac{AB}{AC} \ = \ sin30º \)

=> \( \frac{AB}{20} \ = \ \frac{1}{2} \) [ \( \because sin30º \ = \ \frac{1}{2} \) ]

=> \( AB \ = \ \frac{1}{2} \ × \ 20 \ = \ 10 \)

\(\therefore \) Height of the pole is 10 m.