Basic Theory
Electric Power Calculation
Electric Power Calculation Definition of Electric Power Electric power is the rate at which electrical energy is converted to other forms of energy, representin…
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PowerElectrical energyElectricity costCalculation
Electric Power Calculation
Definition of Electric Power
Electric power is the rate at which electrical energy is converted to other forms of energy, representing the amount of work done per unit time.
Basic Formulas
P = V × I = I² × R = V² / RUnit Conversions
DC Circuit Power
P = V × IAC Circuit Power
Active Power
P = V × I × cos(φ)Unit: Watt (W)
Reactive Power
Q = V × I × sin(φ)Unit: Var
Apparent Power
S = V × IUnit: Volt-Ampere (VA)
Power Triangle
S² = P² + Q²Practical Applications
Calculating Electricity Cost
Cost = Power (kW) × Time (h) × RateExample
A 100W light bulb is used for 10 hours. What is the electricity cost? (Rate: 0.5 yuan/kWh)
Energy consumed = 0.1kW × 10h = 1kWh
Cost = 1kWh × 0.5 yuan/kWh = 0.5 yuan After reading
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