Question

A cylinder with base radius of 8 cm and height of 2 cm is melted to form a cone of height 6 cm. The radius of the cone is

Options

• 4 cm

• 5 cm

• 6 cm

•  8 cm

Answer 1

Volume of cylinder `=pir^2h = pi xx (8)^2 xx 2= 128 pi cm^2`

Let r be the radius of cone

But,

The volume of cone = volume of cylinder

`1/3 pi r^2 h = 128pi`

`r^2 = (128 xx 3)/6 = 64`

 r = 8 cm

Hence, Radius of cone = 8 cm.