The curved surface of a right circular cone of height 15 cm and base diameter 16 cm is :
A. 60π cm2
B. 68π cm2
C. 120π cm2
D. 136π cm2
Answer: Option D
Solution (By Examveda Team)
h = 15 cm, r = 8 cmSo,
$$\eqalign{ & l = \sqrt {{r^2} + {h^2}} \cr & \,\,\,\,\,\, = \sqrt {{8^2} + {{\left( {15} \right)}^2}} \cr & \,\,\,\,\,\, = 17\,cm \cr} $$
∴ Curved surface area :
$$\eqalign{ & = \pi rl \cr & = \left( {\pi \times 8 \times 17} \right){\text{ c}}{{\text{m}}^2} \cr & = 136\pi {\text{ c}}{{\text{m}}^2} \cr} $$

Join The Discussion