JEE Mains · Physics · STD 12 - 1. Electric charges and fields
Three charged particle \(A, B\) and \(C\) with charges \(-4 q, 2 q\) and \(-2 q\) are present on the circumference of a circle of radius \(d\). the charged particles \(A, C\) and centre \(O\) of the circle formed an equilateral triangle as shown in figure. Electric field at \(O\) along \(x-\)direction is
- A \(\frac{2 \sqrt{3} q}{\pi \varepsilon_{0} d^{2}}\)
- B \(\frac{\sqrt{3} \mathrm{q}}{4 \pi \varepsilon_{0} \mathrm{d}^{2}}\)
- C \(\frac{3 \sqrt{3} \mathrm{q}}{4 \pi \varepsilon_{0} \mathrm{d}^{2}}\)
- D \(\frac{\sqrt{3} q}{\pi \varepsilon_{0} d^{2}}\)
Answer & Solution
Correct Answer
(D) \(\frac{\sqrt{3} q}{\pi \varepsilon_{0} d^{2}}\)
Step-by-step Solution
Detailed explanation
\(\mathrm{E}_{\mathrm{x}}=\frac{\mathrm{K}(4 \mathrm{q})}{\mathrm{R}^{2}} \cos 30^{\circ}+\frac{\mathrm{K}(2 \mathrm{q})}{\mathrm{R}^{2}} \cos 30^{\circ}+\frac{\mathrm{K}(2 \mathrm{q})}{\mathrm{R}^{2}} \cos 30^{\circ}\)
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