A Uniform Rule that Can Replace the Left-Hand Rule and the Right-Hand Rule in Electromagnetics

The left-hand rule and the right-hand rule are widely used in electromagnetics but are often confusing. Based on an analysis of the differences and commonalities of the two rules, a uniform rule using coordinate rotation is proposed to determine the direction of the magnetic force and the induced electromotive force (emf) or the induced current in a static magnetic field. Furthermore, we discuss how to use the uniform rule to determine the direction of the induced emf or current in a moving magnetic field, which is traditionally determined by Lenz's law. The uniform rule is easy to understand and remember.