Question

Sphere of diameter 7cm and cut it into two halves . what is the total surface area

Answer 1

4πr²=surface area of sphere

So,

⇒4*22/7 *3.5(because radius is 1/2 of diameter)²=153.94 cm²

When it is cut in half it gets more surface area of the the perimeter of 2 circle's with radius 3.5 aswell,i.e

2πr=2*22/7*3.5=22cm²

Therefore total surface area is 154cm²(approx)+22cm²=176cm².

Answer 2

4πr²=surface area of sphere

So,

⇒4*22/7 *3.5(because radius is 1/2 of diameter)²=153.94 cm²

it is cut in half it gets more surface area of the the perimeter of 2 circle's with radius 3.5 aswell,i.e

2πr=2*22/7*3.5=22cm²

total surface area is 154cm²(approx)+22cm²=176cm².