Question

A vessel is in the form of a hollow hemisphere mounted by a hollow cylinder. The diameter of the hemisphere is 14 cm, and the total height of the vessel is 13cm. Find the inner surface area of the vessel.

Answer 1

Given: Diameter of the hemisphere = 14cm

∴ Radius of the hemisphere = 14/2 = 7 cm

Curved Surface Area of Hemisphere = 2πr²

= 2 x 22/7 x 7 x 7

= 308cm²

Now,

Radius of cylinder = radius of hemisphere = 7cm

Height of cylinder = Total height – Radius of hemisphere

= 13 – 7

= 6cm

So, CSA of cylinder = 2πrh

= 2 x 22/7 x 7 x 6

= 264cm²

The inner Surface area of the vessel

= CSA of hemisphere + CSA of cylinder

= 308 + 264

= 572cm²

Hence, Inner surface area of vessel is 572cm²