Question

A heap of rice is in the form of a cone of diameter 9 m and height 3.5 m. Find the volume of the rice. How much canvas cloth is required to just cover the heap?

Answer 1

According to the question,

Consider conical heap,

Base Diameter = 9 cm

So, base radius, r = 4.5 cm

Height, h = 3.5 cm

We know that,

Slant height,

The equation of volume of cone = 1/3πr²h

We know that,

Volume of rice = Volume of conical heap

Volume of rice = 1/3π(4.5)²(3.5)

We also know that,

Canvas requires to just cover heap = Curved surface area of conical heap

And curved surface area of a cone = πrl

Therefore, the canvas required = π(4.5)(5.7) = 80.61 cm² [appx]