question_answer

Two point dipoles \[p\hat{k}\] and \[\frac{P}{2}\hat{k}\] are located at (0, 0, 0) and (1m, 0, 2m) respectively. The resultant electric field due to the two dipoles at the point (1m, 0, 0) is

A) \[\frac{9P}{32\pi {{\in }_{0}}}\hat{k}\]

B) \[\frac{-7P}{32\pi {{\in }_{0}}}\hat{k}\]

C) \[\frac{7P}{32\pi {{\in }_{0}}}\hat{k}\]

D)  \[\frac{6P}{{{\in }_{0}}}\hat{k}\]

Correct Answer: B

Solution :

[b] The given point is at axis of \[\frac{{\vec{p}}}{2}\] dipole and at equatorial line of \[\vec{p}\] dipole so that field at given point is