Question

radius of sphere is r centimetre it is divided into two equal parts find the whole surface of two parts

Answer 1

Hey there,
Radius of  a sphere = rcm
If the sphere is divided into two equal parts, then the resulting parts are hemispheres with radius rcm.
Total surface area of each hemisphere = 3πr2
Total surface area of both parts = 2 x 3π2 = 6πr2
Hence, the whole surface areas of two parts is 6πr2 

Hope this helps! 

Answer 2

Heya,

Assume that the radius of the sphere = r

Given:-

Sphere is divided into 2 equal parts = 2 (hemisphere)

TSA of hemisphere = 3πr^2
[it is given that the sphere is divided into 2 parts]

Therefore,

TSA of both hemisphere = 2 (3πr^2)
TSA of both hemisphere = 6πr^2

=> Hence the whole surface area of the two parts is 6πr^2

Hope my answer helps you :)

Regards,
Shobana