Question

a solid sphere of radius R centimetre is cut into two equal halves the ratio between the surface area of the first to the total surface area of both the pieces so obtained is

Answer 1

let, radius of first sphere= 2r
radius of sphere when it is halved
=r
thus, ratio of full sphere with redprct to halved sphere
= 4×22/7×(2r)^2:2×4×22/7×(r)^2
=2:1
required ratio is 2:1

Answer 2

Answer: 2:1

Step-by-step explanation:

area of sphere is = $\frac{4}{3} \pi R^{3}$

sphere is cut into two equal parts.

area of semi sphere = $\frac{2}{3} \pi R^{3}$

so ratio of sphere and semi sphere= 2:1