JEE Mains · Physics · STD 12 - Electric charges and fields
- JEE Mains 2026
- Easy
- MCQ
Two shorts dipoles \((A, B), A\) having charges \(\pm 2 \mu C\) and length 1 cm and \(B\) having charges \(\pm 4 \mu C\) and length 1 cm are placed with their centres 80 cm apart as shown in the figure. The electric field at a point \(P\), equi-distant from the centres of both dipoles is ___________ N/C.

Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(\frac{9}{16}\sqrt{2}\times10^{4}\)
Step-by-step Solution
Detailed explanation

\(\overrightarrow{ E }_2=-\frac{ KP _2}{ r ^3} ; E _1=-\frac{2 KP _1}{ r ^3}\)
\(P_1=2 \times 10^{-6} \times 10^{-2}=2 \times 10^{-8}\)
\(P_2=4 \times 10^{-6} \times 10^{-2}=4 \times 10^{-8}\)
\(\overrightarrow{ E }_{\text {net }} \frac{2 \times 9 \times 10^9 \times 2 \times 10^{-8}}{(0.4)^3} \hat{ i }-\frac{9 \times 10^9 \times 4 \times 10^{-8}}{(0.4)^3} \hat{ j }\)
\(\overrightarrow{ E }_{\text {net }}=\frac{9 \times 10^9 \times 4 \times 10^{-8}}{(0.4)^3}[\hat{ i }-\hat{ j }]\)
\(\left|\overrightarrow{ E }_{\text {net }}\right|=\frac{9 \times 10^4}{16}(\sqrt{2})\)
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