The Lorentz force law describes how charged particles move in electric and magnetic fields. It states that the force acting on a charged particle is equal to the sum of the electric force and the magnetic force. The electric force is proportional to the charge and the electric field, while the magnetic force depends on the charge, its velocity, and the magnetic field. Mathematically, the Lorentz force can be expressed as F = q(E + v × B), where F is the total force, q is the charge, E is the electric field, v is the velocity of the particle, and B is the magnetic field. This law is fundamental in understanding the behavior of particles in electromagnetic fields.