JEE Mains · Physics · STD 12 - 1. Electric charges and fields
A point charge of \(10\,\mu C\) is placed at the origin. At what location on the \(X\)-axis should a point charge of \(40\,\mu\,C\) be placed so that the net electric field is zero at \(x =2\,cm\) on the \(X\)-axis ?
- A \(x =6\,cm\)
- B \(x=4\,cm\)
- C \(x =8\,cm\)
- D \(x=-4\,cm\)
Answer & Solution
Correct Answer
(A) \(x =6\,cm\)
Step-by-step Solution
Detailed explanation
\(E _{ P }=\frac{ K \times 10}{2^2}-\frac{ K \times 40}{\left( x _0-2\right)^2}=0\) \(\frac{1}{2}=\frac{2}{x_0-2}\) \(x_0-2=4\) \(x_0=6\,cm\)
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