Alternating Current

Sinusoidal Signals (3)

  • If a sinusoid is applied to a resistor, power will be dissipated as heat.
        P = V2 ÷ R for d.c.
  • The effective voltage (equivalent d.c.voltage) for a sinusoid is called the rms voltage (root mean square)
    This is voltage normally indicated by an a.c. voltmeter.
    Vrms = 0.707 Vmax ;   and   Vmax = 1.414 Vrms
  • So    P = Vrms2 ÷ R  for a.c.