Lorentz force The force acting on a charge q moving with velocity, V at a point in space is the sum of forces due to the electric field, E and the magnetic field, B existing at that point. The expression of the force is given by,

F = q ( E + V´ B )

is called the Lorentz force. When the unit of electric field, E is volt per meter, for magnetic field, B, called the magnetic flux density, weber per square meter, and for charge q coulomb, the force will be in newton. The magnitude of the force is the same in any inertial frame*.