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Page 9

| Figure 1-8 A basic alternator. |

| In a 60-cycle system, each cycle or two alternations takes place in 1/60 second. |

| An electrical pressure can be induced in a conductor by moving it through a magnetic field as described above. A voltage can also be induced electromagnetically by moving a magnetic field across the conductor. (Fig. 1-8.) |

| It makes no difference whether the conductor is moved across the magnetic field or if the magnetic field is moved across the conductor. A stationary conductor which has a magnetic field sweeping across it is cutting a magnetic field just the same as though the conductor was moving across the magnetic field. |

| Inductance |

| A conductor carrying alternating current has a magnetic field around it which alternates its characteristics in accordance with the alternations of the current flowing through the conductor. Following the sine wave characteristic of the alternating current, the magnetic field produced is zero at the start, builds up to a maximum in one direction at the first-quarter cycle, as shown in Fig. 1-9A, B, C, and D (on page 10) respectively, and reduces to zero at the second-quarter cycle, as shown in Fig. 1-9D, C, B, and A respectively, builds up again to a maximum in the third-quarter cycle but in a direction opposite to the previous maximum, and reduces to zero again to complete the cycle. |

| Self-Inductance |

| The expansion and contraction of the magnetic field constitutes a moving magnetic field which cuts the conductor carrying the current producing it. Such action will produce a voltage in the conductor distinct from, and tending to oppose that causing the original current to flow. This second voltage also |

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