Polarity of a Single Conductor

Basic Electrical Theory MAGNETISM Electromagnetism The relationship between magnetism and electrical current was discovered by a Danish scientist named Oersted in 1819. He found that if an electric current was caused to flow through a conductor, the conductor produced a magnetic field around that conductor (Figure 21). Figure 21 The Magnetic Field Produced by Current in a Conductor Polarity of a Single Conductor A convenient way to determine the relationship between the current flow through a conductor and the direction of the magnetic lines of force around the conductor is the left-hand rule for current carrying conductors, as illustrated in Figure 22. The student should verify that the left- hand rule holds true for the examples shown in Figure 21. Figure 22 Left-hand Rule for Current Carrying Conductors Rev. 0 Page 31 ES-01