Question

3. Calculate the surface area of sphere whose radius is 10 cm.​

Answer 1

Answer:

Step-by-step explanation:

the surface area of a sphere of radius r is 4  πr2  

Half of this is  2πr2  

Which is the area of hemisphere

The area of a circle of radius r is  πr2  

thus if the hemisphere is meant to include the base then the surface area is

2πr2+πr2=3πr2  

Hence in this case  3πr2=3×π×102=942.477796..

Answer 2

$\bf \huge {\underline {\underline \red{AnSwEr}}}$

Given

• Radius of sphere = 10cm

To Calculate

• Surface area of sphere

Solution

Surface area of Sphere

$\bf \blue{ \implies 4\pi {r}^{2} }$

$\bf \pink{\implies 4 \times \frac{22}{7} \times {10}^{2} }$

$\bf \blue{ \implies 4 \times \frac{22}{7} \times 100 }$

$\bf \pink{ \implies \frac{8800}{7} }$

$\bf \blue{ \implies 1257 \frac{1}{7} {cm}^{2} }$