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11.4 Chapter summary

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11.4 Chapter summary (ESCQG)

Presentation: 27YS

  • Electrical generators convert mechanical energy into electrical energy.

  • Electric motors convert electrical energy into mechanical energy.

  • There are two types of generators - AC and DC. An AC generator is also called an alternator.

  • There are two types of motors - AC and DC.

  • Alternating current (AC) has many advantages over direct current (DC) listed previously.

  • The root mean square (rms) value of a quantity is the maximum value the quantity can have divided by \(\sqrt{\text{2}}\).

  • RMS values are used for voltage and current when dealing with alternating current, \(I_{\text{rms}} = \dfrac{I_{\text{max}}}{\sqrt{\text{2}}}\) and \(V_{\text{rms}} = \dfrac{V_{\text{max}}}{\sqrt{\text{2}}}\).

  • The average power dissipated in a purely resistive circuit with alternating current is \(P_{av}=I_{rms}V_{rms}\).