Physics

Problem

As per this diagram a point charge

+q

is placed at the origin O. Work done in taking another point charge

-q

from the point A [co-ordinates

(0,a)

] to another point B [co-ordinates

(a,0)

] along the straight path AB is: a. Zero b.

\left(\frac{-qQ}{4\pi\epsilon_0}\right)\left(\frac{1}{a^2}\right)\sqrt{2}a

\left(\frac{qQ}{4\pi\epsilon_0}\right)\left(\frac{1}{a^2}\right)\cdot \frac{a}{\sqrt{2}}

\left(\frac{qQ}{4\pi\epsilon_0}\right)\left(\frac{1}{a^2}\right)\sqrt{2}a