Two point charges q1 and q2 placed a distance r apart The el

Two point charges, q_1 and q_2 placed a distance r apart. The electric field is zero at a point P between the charges on the line segment connecting them. We conclude that: q_1 and q_2 must have the same magnitude and sign P must be midway between q_1and q_2 q_1 and q_2 must have opposite signs and may have different magnitudes q_1 and q_2 must have equal magnitudes and opposite signs q_1 and q_2 must have the same sign but may have different magnitudes A dipole with charge of plusminus 3mu C is centered at the origin and the dipole moment is oriented along the +x-axis. The charge separation is 0.001-m. Find the electric field d to this dipole at the point x=4.0m, y=0.0m. 1100 i N/C 0.84 l N/C 0.42 1 N/C -0.42 l N/C -0.84 1 N/C None of the above

Solution

3) Option D is the correct option

           two charges should be opposite and should have equal mangitude in order to have zero electric field at centre.So Option D is correct.(q1 and q2 must have equal mangitude and opposite sign ).

4) E = KP / r³

      E = (9* 10⁹) (qd) / r³ = (9* 10⁹) (3*10^-6)(0.001) / 4³

       E = 0.42i

SO , option C is correct opiton