Figure 2245 shows an electric dipole What are the magnitude

Figure 22-45 shows an electric dipole. What are the magnitude and direction (relative to the positive direction of the x axis) of the dipole\'s electric field at point P, located at distance r > d?

Solution

Dipole moment P = 2*d/2*q = qd

Electric field on the perpendicular bisector of the dipole

E = P/4₀ (r² +(d/2)² )^3/2

given r>>d , we can ignore (d/2)² compared to r²

E = P/4₀r³ = qd/4₀r³

direction of the field is -ve y-axis