JEE Mains · Physics · STD 12 - 1. Electric charges and fields
Four point charges \(-q, +q, +q\) and \(-q\) are placed on \(y\) axis at \(y = -2d\), \(y = -d, y = +d\) and \(y = +2d\), respectively. The magnitude of the electric field \(E\) at a point on the \(x -\) axis at \(x = D\), with \(D > > d\), will vary as
- A \(E \propto \frac{1}{D}\)
- B \(E \propto \frac{1}{D^3}\)
- C \(E \propto \frac{1}{D^2}\)
- D \(E \propto \frac{1}{D^4}\)
Answer & Solution
Correct Answer
(D) \(E \propto \frac{1}{D^4}\)
Step-by-step Solution
Detailed explanation
Electric field at \(\mathrm{p}=2 \mathrm{E}_{1} \cos \theta_{1}-2 \mathrm{E}_{2} \cos \theta_{2}\)…
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