Question

The law of repulsion by Coulomb agrees with:

Answer 1

In Coulomb's law, however, the magnitude and sign of the electric force are determined by the electric charge, rather than the mass, of an object. ... Thus, two negative charges repel one another, while a positive charge attracts a negative charge. The attraction or repulsion acts along the line between the two charges

Answer 2

Answer & explanation:

Coulomb's law refers to the forces of interaction (attraction and repulsion) between two punctual electrical charges, that is, with negligible size and mass.

According to the principle of attraction and repulsion, charges with opposite signs are attracted and with equal signs are repelled, but these interaction forces have equal intensity, regardless of the direction in which the vector describing them points.  

Through laboratory measurements, Coulomb determined that the value of the modulus of force that exists between two charged spheres, one charge (Q1) and another charge (Q2), is proportional to the product, in modulus, of its loads and inversely proportional to the square of the charge in a distance d between them. This can be described in the following equation:

$F = k * (|Q1| * |Q2|) / d^2$

Where F is the force between the charges, Q₁ and Q₂ being the modulus of the charges of the spheres and d is the distance between them, while k is called the electrostatic constant.