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5.6: Magnetic Fields and Forces

  • Page ID
    32773
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    Currents (moving charges) create magnetic fields. The familiar refrigerator magnetic has moving charges that create its magnetic field (electrons orbiting the nucleus of the atom), but we don't have a complete understanding of why different materials have different magnetic properties. In this chapter we won't worry about what creates the magnetic field and will focus instead on i.) describing magnetic fields (with field vectors, a compass, and field lines) and ii.) the effect of magnetic fields on charged particles (the Lorentz force). We will map magnetic field lines because that tells us about the forces between magnets (that like poles repel). Further, we will explore the force that a charged particle experiences in a magnetic field. This force depends not only on the magnitude of the magnetic field, but on the speed of the particle as well as its orientation in the magnetic field.