JEE Mains · Physics · STD 12 - 1. Electric charges and fields
Find out the surface charge density at the intersection of point \(x =3\, m\) plane and \(x\) -axis, in the region of uniform line charge of \(8\, nC / m\) lying along the \(z\) -axis in free space.
- A \(0.424 \,n\,C m ^{-2}\)
- B \(47.88 \,C / m\)
- C \(0.07\, n\,C m ^{-2}\)
- D \(4.0\, n\,C m ^{-2}\)
Answer & Solution
Correct Answer
(A) \(0.424 \,n\,C m ^{-2}\)
Step-by-step Solution
Detailed explanation
\(\frac{2 K \lambda}{ r }=\frac{\sigma}{\varepsilon_{0}}\) \(\quad(x=3 \,m)\) \(\sigma=0.424 \times 10^{-9}\, \frac{ C }{ m ^{2}}\)
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