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Question
Find the magnitude of the electric field at the point P in the configuration shown in the figure for d >> a.
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Solution
Taking
\[\text{ So}, E = E_1 \cos \theta + E_2 cos\theta\]
\[ = E_1 cos\theta + E_2 cos\theta\]
\[ = 2 E_1 \cos \theta\]
\[ = 2 . \frac{1}{4\pi \in_0} . \frac{qa}{( d^2 + a^2 )^{3/2}}\]
\[ = \frac{1}{4\pi \in_0} . \frac{p}{d^3} [\text{ since } a < < d]\]
Notes
Figure is missing in the question .
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