Physics

Problem

Let

E_1(r)

E_2(r)

and

E_3(r)

be the respective electric field at a distance

r

from a point charge

Q

, an infinitely long wire with constant linear charge density

\lambda

, and an infinite plane with uniform surface charge density

\sigma

. If

E_1(r_0) = E_2(r_0) = E_3(r_0)

at a given distance

r_0

, then [Adv. 2014] a.

Q = 4\sigma\pi r_0^2

r_0 = \frac{\lambda}{2\pi\sigma}

E_1(r_0/2) = 2E_2(r_0/2)

E_2(r_0/2) = 4E_3(r_0/2)