Q: A spherical shell of outer radius R and inner radius R/2 contains a solid sphere of radius R/2 (see figure). The density of the material of the solid sphere is ρ and that of the shell is ρ/2. What is the average mass density of the larger sphere thus formed?
(a)3ρ/4
(b)9ρ/16
(c)7ρ/8
(d)5ρ/8
Correct Answer: (b)
The correct answer is (b): 9ρ/16. Subject: General Studies | Sub-topic: Miscellaneous