WBJEE · Physics · Magnetic Effects of Current
Two infinite line-charges parallel to each other are moving with a constant velocity \(v\) in the same direction as shown in the figure. The separation between two line-charges is \(d\). The magnetic attraction balances the electric repulsion when, [c = speed of light in free space]
- A \(\quad v=\sqrt{2} c\)
- B \(v=\frac{c}{\sqrt{2}}\)
- C \(v=c\)
- D \(v=\frac{c}{2}\)
Answer & Solution
Correct Answer
(C) \(v=c\)
Step-by-step Solution
Detailed explanation
\(\mathrm{F}_{\mathrm{E}}=\mathrm{q}_2 \mathrm{E}_1=\lambda_2 \ell \frac{2 \mathrm{k} \lambda_1}{\mathrm{~d}}\)…
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