Question

1 point
11. The diameter of cylinder is
28 cm and its height is 20 cm
.then its curved surface area is
O 880 sq. cm
O 1760 sq. cm
O 3520 sq. cm
0
O
2640 sq. cm​

Answer 1

☆Required Answer:-

• Option b. 1760sq.cm

Given:-

• The diameter of cylinder is 28 cm and its height is 20 cm.

To Find:-

• Find the curved surface area (CSA) of the cylinder.

Concept:-

• Let's go through the concept first. Concept used here is Curved Surface Area (CSA) of a Cylinder.Substitute the given values in the equation and solve it out.

Formulae Applied:-

• Curved Surface Area (CSA) of a Cylinder = 2πrh

Solution:-

Diameter = 28cm

Radius = 28/2 = 14cm

Height = 20cm

CSA = ??

According to the question we have!

Curved Surface Area (CSA) of a Cylinder = 2πrh

⟹ 2πrh

⟹ 2 × 22/7 × 14 × 20

⟹ 2 × 22 × 2 × 20

⟹ 44 × 40

⟹ 1760

⟹ 1760cm^2

Hence,

The CSA of the cylinder is 1760cm^2.

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Answer 2

please refer ncert books