As per the diagram, a point charge +q is placed at the origin O. Work done in taking another point charge −Q from the point A[ coordinates (0, a)] to another point B [coordinates (a, 0)] along the straight path AB is ?

As per the diagram, a point charge +q is placed at the origin O. Work done in taking another point charge −Q from the point A[ coordinates (0, a)] to another point B [coordinates (a, 0)] along the straight path AB is ?

(a) \( 0 \)

(b) \( -\frac{qQ}{4\pi \varepsilon_0} \cdot \frac{1}{a^2} \cdot \sqrt{2a} \)

(c) \( \frac{qQ}{4\pi \varepsilon_0} \cdot \frac{1}{a^2} \cdot \frac{\sqrt{a}}{2} \)

(d) \( \frac{qQ}{4\pi \varepsilon_0} \cdot \frac{1}{a^2} \cdot \sqrt{2a} \)

Answer :  (a) \( 0 \)

\( \text{Work} = \Delta U \)

\( \quad = U_f - U_i \)

\( \quad = 0 \)