Oppositielading

Oppositielading refers to a pair of electric charges whose signs are opposite, typically denoted as a positive and a negative charge. When two charges have opposite signs, they attract each other rather than repel. The interaction strength depends on the magnitudes of the charges and the distance between them.

The magnitude of the electrostatic force between two point charges q1 and q2 separated by a distance r is given by F = k |q1 q2| / r^2, where k is Coulomb's constant. The force is directed along the line joining the charges and is attractive if the charges have opposite signs. The potential energy of the pair is U = k q1 q2 / r, which is negative for opposite charges, reflecting the bound nature of the interaction.

In the context of electric fields, opposite charges set up a dipole field: field lines emerge from the positive charge and terminate at the negative charge. The dipole moment p = q d (where q is the charge magnitude and d is the separation vector from negative to positive) is a measure of the separation of positive and negative charges within a system. Oppositielading is a central concept in electrostatics and underpins many phenomena in chemistry and physics, including ionic bonding, polar molecules, and the behavior of capacitors.

Common contexts include atoms and ions (electrons bound to nuclei, cations and anions in compounds), molecular polarity (water molecules exhibit opposite charges distributed within the molecule), and electrostatic applications (energy storage in capacitors, electrostatic shielding). The concept is contrasted with like charges, which repel each other.