Question

The curved surface area of the largest right circular cone that can be carved out from a solid cube of edge $4	ext{ cm}$ is:

Accepted Answer

A. For the largest cone carved out of a cube of edge $a = 4	ext{ cm}$: - Base diameter $= 4	ext{ cm} \implies r = 2	ext{ cm}$ - Height $h = 4	ext{ cm}$ - Slant height $l = \sqrt{r^2 + h^2} = \sqrt{2^2 + 4^2} = \sqrt{20} = 2\sqrt{5}	ext{ cm}$ $$	ext{CSA} = \pi r l = \pi 	imes 2 	imes 2\sqrt{5} = 4\sqrt{5}\pi	ext{ cm}^2$$

Curved surface area of largest cone carved from a cube

Explanation

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