How does an electric dipole behave in an electric field?
Similarly one may ask, what is an electric dipole what is its direction?
The electric dipole moment, a vector, is directed along the line from negative charge toward positive charge. Dipole moments tend to point along the direction of the surrounding electric field.
Then, what happens when an electric dipole is placed in uniform electric field?
When an electric dipole is places in a uniform electric field , it experiences no force as the electric force on both the negative and the positive charge are equal in magnitude but opposite in direction so they cancel out. But , it experiences a torque(couple) and hence it rotates.
The electric field will apply a force to +e in the direction of the electric field and a force to -e in the direction opposite the electric field. This will rotate the electric dipole. Recall from Physics 1250 that torque is defined as τ=r×F.