COMEDK · Physics · 17. Electrostatics
Point charges \(-3 \mathrm{Q},-\mathrm{q}, 2 \mathrm{q}\) and 2 Q are placed, one at each corner of a square. The relation between Q and q for which the potential at the centre of the square is zero is
- A \(Q=\dfrac{-1}{q}\)
- B \(Q=q\)
- C \(Q=-q\)
- D \(Q=\dfrac{1}{q}\)
Answer & Solution
Correct Answer
(B) \(Q=q\)
Step-by-step Solution
Detailed explanation
Let the side length of the square be \(a\). The distance from each corner to the center of the square is \(r = \dfrac{a}{\sqrt{2}}\). The electric potential \(V\) at the center due to a point charge \(q_i\) at distance \(r\) is given by \(V_i = \dfrac{k q_i}{r}\), where…
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