JEE Mains · Physics · STD 12 - Electric charges and fields
- JEE Mains 2022
- Medium
- MCQ
The three charges \(q / 2, q\) and \(q / 2\) are placed at the corners \(A , B\) and \(C\) of a square of side ' \(a\) ' as shown in figure. The magnitude of electric field \((E)\) at the comer \(D\) of the square, is
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(\frac{ q }{4 \pi \epsilon_{0} a ^{2}}\left(\frac{1}{\sqrt{2}}+\frac{1}{2}\right)\)
Step-by-step Solution
Detailed explanation
\(\left( E _{\text {ner }}\right)_{D}=\frac{ kq }{2 a ^{2}}+\frac{\sqrt{2 kq }}{2 a ^{2}}\)
\(\left( E _{\text {ner }}\right)_{ D }=\frac{ kq }{ a ^{2}}\left(\frac{1}{2}+\frac{1}{\sqrt{2}}\right)\)
\(\left( E _{\text {net }}\right)_{ D }=\frac{ q }{4 \pi \epsilon_{0} a ^{2}}\left(\frac{1}{2}+\frac{1}{\sqrt{2}}\right)\)
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