Q. Two spherical conductors A and B of radii 1mm and 2mm are separated by a distance of 5cm and are uniformly charged. If the spheres are connected by a conducting wire then in equilibrium condition, the ratio of the magnitude of the electric fields at the surfaces of spheres A and B is
A) 4:1
B) 1;2
C) 2:1
D) 1:4
Explanation
(a) When the two conducting spheres are connected by a conducting wire, charge will flow from one sphere (having higher potential) to other (having lower potential) till both acquire the same potential.
$E = \frac{1}{4\pi\varepsilon_{0}}.\frac{q}{r^{2}}$
So,
$\frac{E_{1}}{E_{2}} = \left( \frac{r_{2}}{r_{1}} \right)^{2} = 4:1\ $
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.