Final answer:
In the scenario of a charge -q placed equidistant from an electric dipole with charges +2q and -2q, the forces exerted by the dipole charges cancel out due to symmetry, resulting in a net force of zero.
Step-by-step explanation:
The subject of this question is Physics, specifically relating to the concept of electric charges and Coulomb's law. The force between two point charges can be calculated using Coulomb's law, which states that the force is proportional to the product of the charges and inversely proportional to the square of the distance between them. When considering the direction of the net force on a charge in an electric dipole, one must consider the vector nature of the forces. If a charge is equidistant from two opposite charges of a dipole, the forces exerted by each charge on the third charge will be in opposite directions and their magnitudes will depend on the values of the charges involved.
In the case of a charge -q placed equidistant from a dipole with charges +2q and -2q, the attractive and repulsive forces will be equal in magnitude due to the symmetry of the setup, but they will be in opposite directions. Since the charges are equal and opposite, and the distances are equal, the net force on the charge -q will be zero. This demonstrates an important principle in electrostatics about the balance of forces in symmetrical charge distributions.