dipólus

Dipólus refers to a system consisting of two equal and opposite electric charges separated by a finite distance, forming an electric dipole. The electric dipole moment p is defined as p = q d, where q is the magnitude of the charge and d is the vector from the negative to the positive charge. For a distribution of charges, p = sum q_i r_i. At distances large compared with the separation, the field of a dipole falls off as 1/r^3 and the potential behaves like p·r̂/(4πε0 r^2). In an external uniform electric field E, the dipole experiences a potential energy U = -p·E and a torque τ = p × E that tends to align the dipole with the field.

In chemistry and molecular physics, many molecules have a net dipole moment and are described as polar. The dipole moment is a measure of molecular polarity and is commonly expressed in Debye; 1 Debye ≈ 3.33564×10^-30 C·m. Water is a classic polar molecule with a sizable dipole moment.

Magnetic dipólus, or magnetic dipole moment μ, arises from circulating currents or particle spin and interacts with magnetic fields. Magnetic dipoles generate fields that decay as 1/r^3 and are central to magnetism, electron paramagnetic resonance, and nuclear magnetic resonance. In materials science, dipoles can form spontaneous polarization in ferroelectric materials, contributing to dielectric properties.