JEE Mains · Physics · STD 12 - 1. Electric charges and fields
Three charges +2q. +3q and -4q are situated at (0,-3a), (2a, 0) and (-2a,0) respectively in the xy plane. The resultant dipole moment about origin is _________
- A \( 2qa(3\hat{j}-\hat{i}) \)
- B \( 2qa(3\hat{i}-7\hat{j}) \)
- C \(2 qa (7 \hat{ i }-3 \hat{ j })\)
- D \(2 q a(3 \hat{j}-7 \hat{i})\)
Answer & Solution
Correct Answer
(C) \(2 qa (7 \hat{ i }-3 \hat{ j })\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ p }= q _1 \overrightarrow{ r }_1+ q _2 \overrightarrow{ r }_2+ q _3 \overrightarrow{ r }_3\) \(\overrightarrow{ p }=(2 q)(-3 a) \hat{j}+(3 q)(2 a) \hat{i}+(-4 q)(-2 a) \hat{i}\) \(\overrightarrow{ p }=2 qa (7 \hat{ i }-3 \hat{ j })\)
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