Question

find the volume of a right circular cylinder which has a height of 21cm and the base radius of 5cm. also find the curved surface area of the cylinder.

Answer 1

Volume = π r²h
 = 22/7 × 5² × 21 = 1650 cm ³
 C.S.A = 2πrh
          = 2 × 22 / 7 ×5×21 = 660 cm²

Answer 2

Given:

Height of cylinder=21cm

The radius of base=5 cm

To find:

The volume and curved surface area of the cylinder

Solution:

The volume and curved surface area of the cylinder are 1,650 $cm^{3}$ and 660$cm^{2}$, respectively.

We can find the volume and area by following the steps given-

We know that the curved surface area of a cylinder excludes the area of the top and bottom of the cylinder.

The height of the cylinder, H=21cm

The radius of the base of the cylinder, R=5cm

Now, the volume of the cylinder=π$R^{2}$H

On putting the values,

=22/7×25×21

=22×25×3

=1,650 $cm^{3}$

Similarly, we will calculate the curved surface area.

The curved surface area of the cylinder=2πRH

=2×22/7×5×21

=2×22×5×3

=660$cm^{2}$

Therefore, the volume and curved surface area of the cylinder are 1,650 $cm^{3}$ and 660$cm^{2}$, respectively.