Question

A vessel is in the form of a frustum of a cone. Its diameter at top end is 2 m and the bottom end is 0.5 m. Its height is 5 m. Find the volume of the frustum cone. (Use $\pi$ = 3).

• A. 1.3125 $m^3$
• B. 2.3125 $m^3$
• C. 6.5625 $m^3$
• D. 4.3125 $m^3$

Answer 1

The correct option is C 6.5625 $m^3$

Volume of a frustum cone = $\frac{\pi h}{3}(R^2+Rr+r^2)$

Diameter = radius $\times 2$

Radius, R = 1 m, r = 0.25 m

= $\frac{3\times 5}{3}(1^2+1\times 0.25+{0.25}^2)$

= $5(1+0.25+0.0625)$

= $5\left(1.3125\right)$

= 6.5625 $m^3$