If the base radius of a cone is 7 cm and height of it is 14 cm, then:
A. Slant height = $6\sqrt{5}$cm
B. Slant height = $7\sqrt{5}$cm
C. Volume = 718.67 cm3
D. Volume = 708.66 cm3
E. Ratio of height and slant height = $2:\sqrt{5}$
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
i) Slant height of cone = \(\sqrt {r^2 + h^2}\) = \(\sqrt {7^2 + 14^2}\) = \(\sqrt {49 + 196}\) = \(\sqrt {245}\) = 7\(\sqrt {5}\)
ii) Volume = \(\frac{1}{3}\) \(\pi \)r2h = \(\frac{1}{3}\) × \(\frac{22}{7}\) ×7 × 7 × 14 = 718.67
iii) Ratio of height and slant height = 14 : 7\(\sqrt {5}\) = $2:\sqrt{5}$
Therefore,
B, C and E only are correct.