Question

Two identical solid hemispheres of equal base radius r cm are stuck together along their bases. The total surface area of the combination is _________.

Answer 1

When two identical solid hemispheres of equal base radius are stuck together along their bases, then the new solid so formed is a sphere. The radius of the sphere is same as the base radius of each solid hemisphere.

Radius of the sphere = r cm

∴ Total surface area of the combination = Total surface area of sphere = $4\mathrm{\pi }{r}^2$ cm²

Two identical solid hemispheres of equal base radius r cm are stuck together along their bases. The total surface area of the combination is $\underline{4\mathrm{\pi }{r}^2{\mathrm{cm}}^2}$.