Question

the diameter of the base of a right circular cylinder is 10cm and it's height is 21cm find the area of the curved surface and volume of the cylinder​

Answer 1

Answer :

• Curved surface area of cylinder is 660cm²
• Volume of cylinder is 1650cm³

Given :

• The diameter of the base of right circular cylinder is 10cm
• Height of cylinder is 21cm

To find :

• Area of curved surface
• Volume of cylinder

Solution :

First we need to find the radius :

Diameter is 10cm

We know that,

》Radius = Diameter/2

》Radius = 10/2

》Radius = 5cm

Hence , Radius is 5cm

• Radius is 5cm
• Height is 21cm

(1) Curved surface area of cylinder :

As we know that,

• Curved surface area of cylinder = 2πrh

Where, r is radius and h is height

》Curved surface area of cylinder = 2πrh

》2 × 22/7 × 5 × 21

》2 × 22 × 5 × 3

》220 × 3

》660cm²

Hence , Curved surface area of cylinder is 660cm²

(2) Volume of cylinder :

As we know that

• Volume of cylinder = πr²h

》Volume of cylinder = πr²h

》22/7 × (5)² × 21

》22/7 × 5 × 5 × 21

》22 × 5 × 5 × 3

》550 × 3

》1650cm³

Hence , Volume of cylinder is 1650cm³

Answer 2

Given :-

The  diameter of the base of a right circular cylinder is 10cm and it's height is 21cm

To Find :-

CSA

Volume

Solution :-

We know that

Radius = Diameter/2

Radius = 10/2

Radius = 5 cm

Now

CSA = 2πrh

CSA = 2 × 22/7 × 5 × 21

CSA = 44/7 × 5 × 21

CSA = 44 × 5 × 3

CSA = 660 cm³

Now

Volume = πr²h

Volume = 22/7 × (5)² × 21

Volume = 22/7 × 25 × 21

Volume = 22 × 25 × 3

Volume = 1650 cm³