Example problem of a hemisphere — lesson. Mathematics CBSE, Class 9.

UPSKILL MATH PLUS

Learn Mathematics through our AI based learning portal with the support of our Academic Experts!

The diameter of an orange is \(8 \ cm\). Calculate the total surface area of the half orange.

Solution:

Diameter of an orange \((d)\) \(=\) \(8 \ cm\)

Radius of an orange \((r)\) \(=\)

\frac{d}{2} = \frac{8}{2} = 4 cm

A half orange is in the shape of a hemisphere.

Total surface area of a hemisphere \(=\) \(3 \pi r^2\) sq. units

\(=\)

3 \times \frac{22}{7} \times 4^{2}

\(=\)

3 \times \frac{22}{7} \times 16

\(=\) \(150.86\)

Total surface area of the half orange is \(150.86 \ cm^2\).

Important!

The value of \(\pi\) should be taken as \(\frac{22}{7}\) unless its value is shared in the problem.

Did you find an error?

4. Example problem of a hemisphere