Question

Find the surface area of a sphere of diameter:

(i) 14 cm (ii) 21 cm (iii) 3.5 m

Answer 1

(i) Radius (r) of sphere =

Surface area of sphere = 4πr²

Therefore, the surface area of a sphere having diameter 14 cm is 616 cm².

(ii) Radius (r) of sphere =

Surface area of sphere = 4πr²

Therefore, the surface area of a sphere having diameter 21 cm is 1386 cm².

(iii) Radius (r) of sphere = m

Surface area of sphere = 4πr²

Therefore, the surface area of the sphere having diameter 3.5 m is 38.5 m².