JEE Mains · Physics · STD 12 - 1. Electric charges and fields
As shown in figure, a cuboid lies in a region with electric field \(E=2 x^2 \hat{i}-4 y \hat{j}+6 \hat{k} \quad N / C\). The magnitude of charge within the cuboid is \(n \varepsilon_0 C\). The value of \(n\) is \(............\) (if dimension of cuboid is \(1 \times 2 \times 3 \;m ^3\) )
- A \(10\)
- B \(11\)
- C \(12\)
- D \(13\)
Answer & Solution
Correct Answer
(C) \(12\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ E }=2 x ^2 \hat{ i }-4 y \hat{ j }+6 \hat{ k }\) \(\phi_{\text {net }}=-8 \times 3+2 \times 6=-12\) \(-12=\frac{ q }{\epsilon_0}\) \(| q |=12 \epsilon_0\)
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