Question

A right triangle with sides 6 cm, 8 cm and 10 cm is revolved about the side 8 cm. Find the volume and the curved surface of the solid so formed.

Answer 1

When a right triangle with sides 6 cm, 8 cm and 10 cm is revolved about the side 8 cm, then solid formed is a cone whose height of a cone, h = 8 cm and radius of a cone, r = 6 cm. Slant height of a cone, l = 10 cm

Volume of a cone = 1/3 πr²h 

= (1/3) x (22/7) x 6 x 6 x 8

=> 6336/21 = 301.7 cm³ and curved surface of the area of cone = πrl

=> (22/7) x 6 x 10 = 1320/7 = 188.5 cm²

Hence, the volume and surface area of a cone are 301.7 cm³ and 188.5 cm², respectively.