OHM'S LAW and What It Means to Homeowners

P=E*I or Watts =Volts * Amps

This is the most common variation of ohms law for residential electric. Often manufactures will only include two of the the three variables and the electrician or home owner will need to figure out the last quality. Often equipment only has a wattage on it. That is done with the expectation of the end user knows the voltage of their electrical system. In the United States residential lighting circuits usw 120 volts. So a 60watt light bulb divided by 120 volts uses .5amp. 60watt/120Volts=.5amps
Ohm's law electrical chart
  • Voltage = the Square Root of Power * Resistance
  • Voltage = Power / Current
  • Voltage = Current * Resistance
  • Resistance = Voltage / Current
  • Resistance = Power / Current squared
  • Resistance = Voltage squared / Power
  • Current = Voltage / Resistance
  • Current = the Square Root of Power / Resistance
  • Current = Power / Voltage
  • Power = Voltage * Current
  • Power = the Current squared * Resistance
  • Power = the Voltage squared / Resistance

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