Question

From a solid cylinder whose height is 15cm and diameter 16cm, a conical cavity of the same height and same diameter is hollowed out. Find the total surface area of remaining solid. (use π = 3.14).

Answer 1

Height of cylinder is h = 15 cm.

Diameter of cylinder is 2r = 16 cm.

∴ Radius of cylinder is r = \(\frac{16}{2}\) = 8 cm.

Given that cone has same diameter and same height.

∴ Height of the cone is h = 15 cm

& radius of the cone is r = 8 cm

∴ The slant height of the cone is l

∴ The slant height of the cone is l = 17 cm.

∵A conical cavity of same height & same diameter is hollowed out from the given cylinder

∴Total surface area of remaining solid = curved surface area of the cone + surface area of base + surface area of the cylinder.

So, the total surface area of the remaining solid is 1381.6 cm².