Two short dipoles `phat(k)` and `P/2 hat(k)` are located at `(0,0,0)` & `(1m, 0,2m)` respectivley. The resultant electric field due to the two dipoles at the point `(1m, 0,0)` is

Answer

`(-7)/8 kphat(k)`

Explanation

Electric field due to dipole `vec(P)=-(KP)/1^(3)xxhat(k)`
Electric field due to dipole `vec(P)/2=+(2KxxP/2)/2^(3)hat(k)`
Resulatnt electric field `=-7/8 Kphat(k)`