Question

The radius of a cylinder is 14 cm and its height is 7cm.Calculate the total surface area of the cylinder​

Answer 1

Answer:

In volume of cylinder, the radius is multiplied by squaring it.

∴ Volume of cylinder B will be more than that of A

Volume of cylinder A

Radius(r)=

2

7

cm

Height(h)=14 cm

∴Volume of cylinder A=πr

2

h

=

7

22

×(

2

7

)

2

×14cc

=11×7×7=539cc

Volume of cylinder B

Radius(r)=

2

14

cm=7 cm

Height(h)=7 cm

∴Volume of cylinder B=πr

2

h

=

7

22

×(7)

2

×7cc

=22×7×7=1078cc

Thus, cylinder B has greater volume.

Now, Surface area of cylinder A=2πr(r+h)

=2×

7

22

×

2

7

(

2

7

+14)

=22×

2

35

=11×25=385 sq.cm

Now, Surface area of cylinder B=2πr(r+h)

=2×

7

22

×7(7+7)

=2×22×14=616 sq.cm

Thus, the cylinder of greater capacity has greater surface area.

Answer 2

Answer:

Total surface area equals 1848cm²

Step-by-step explanation:

Total surface area = 2πr(h+r)

here radius = 14 cm

height = 7 cm

total surface area =

$2 \times \frac{22}{7} \times 14(14 + 7) \\ = 2 \times \frac{22}{7} \times 14 \times 21 \\ = 2 \times 22 \times 2 \times 21 \\ = 88 \times 21 = 1848 {cm}^{2}$