A vertical rod of height 33 metres is bent to form a semi-circular shape so that the top touches the ground. The distance between the top head and the base on the ground is :

A. 10.5 m

B. 12 m

C. 21 m

D. 33 m

Answer: Option C

Solution(By Examveda Team)

$$\eqalign{ & \pi R = 33 \cr & \Rightarrow R = \left( {\frac{{33 \times 7}}{{22}}} \right) \cr & \Rightarrow R = \left( {\frac{{21}}{2}} \right)m \cr} $$
∴ Required distance = 2R = 21 m