Question

Two spheres have equal surface density of change. If their radius r in the ratio 1:4, Then calculate the ratio of the charge.

Answer 1

As we know that**σ = q/a
In spherical body surface area is equal to4πr 2**

If charge density of both the sphere is equal, than
q1/a1=q2/a2
q1/4πr12=q2/4πr22
q1/r12=q2/r22
from the question r1 & r2 is in the ratio 1:4

q1/1=q2/(4)2
thus
q1/q2=1/16