Magnetic repulsion occurs when the like poles of two magnets face each other, causing them to repel each other. This is because the magnetic field lines of the two magnets oppose each other, creating a force that pushes the magnets apart. The greater the magnetic strength of the magnets, the stronger the repulsion force will be. Magnetic repulsion is a fundamental property of magnets and plays a crucial role in various applications, such as magnetic levitation, MRI, and magnetic bearings.