The volumes of two spheres are in the ratio 64 : 27. The ratio of their surface areas is
(a)1 : 2
(b)2 : 3
(c)9 : 16
(d)16 : 9
Answers
Answer:
The Ratio of their curved surface area is 16 : 9.
Among the given options option (d) 16 : 9 is the correct answer.
Step-by-step explanation:
Given :
Volumes of two spheres in the ratio = 64 : 27
V1 : V2 = 64 : 27
Let the radius of first sphere be r1 and radius of second sphere be r2.
V1 / V2 = 64 / 27
64/27 = (4/3 πr₁³) / (4/3 πr₂³)
64/27 = r₁³/r₂³
4³/3³ = r₁³/r₂³
(r₁/r₂)³ = (4/3)³
r₁/r₂ = 4/3 …. ……..(1)
Ratio of their curved surface area :
curved surface area first sphere, S1 : curved surface area second sphere ,S2= 4πr1² : 4πr2²
S1/S2 = 4πr1²/4πr2²
S1/S2 = r1²/r2²
S1/S2 = (r1/r2)²
S1/S2 = (4/3)²
[FROM EQ 1]
S1/S2 = 16 / 9
S1: S2 = 16 : 9
Ratio of their curved surface area = 16 : 9
Hence, the Ratio of their curved surface area is 16 : 9.
HOPE THIS ANSWER WILL HELP YOU…
Answer :- 16 :9✔️✔️
EXPLANATION : -
Ratio of volumes = (R^3):(r^3)=64:27
=( 4^3) : (3^3)
so, (R) :(r) = 4:3
ratio of surface areas =(R^2) : (r^2)
= (4^2) :(3^2)
=16:9✔️✔️✔️
✌✌✌✌✌✌✌✌