Question

A sphere with radius r is divided into four equal parts. Then, the total surface area
of each of those parts is
A. 4πr^2
В. Злr^2
C. πr^2
D. 2πr^2​

Answer 1

Answer:

4πr^2 is the correct answer

Answer 2

Given,

Radius of sphere = r units

To find,

Total surface area of each parts if the sphere is divided into 4 equal parts.

Solution,

We can easily solve this mathematical problem by using the following mathematical process.

Now, Curved surface area of the sphere = 4πr² sq.unit

Curved surface area of each parts = 4πr²/4 = πr² sq.unit

The two plane edges of one part will be two semicircles with same radius.

Area of those two edges = (πr²/2 + πr²/2) = πr² sq.unit

Total surface area of the one part = (CSA + area of plain edges) = (πr²+πr²) = 2πr² sq. unit

Hence, the total surface area will be 2πr² sq.unit