The Four Ohm's Law Relationships

FindFormulaAlternates
Voltage (V)V = I × RV = P / I, V = √(P × R)
Current (I)I = V / RI = P / V, I = √(P / R)
Resistance (R)R = V / IR = V² / P, R = P / I²
Power (P)P = V × IP = V² / R, P = I² × R

Common Household Values

ApplianceVoltageTypical WattsAmps (@ voltage)
LED bulb120V10W0.08A
Laptop charger120V65W0.54A
Microwave120V1,000W8.3A
Electric stove240V3,000W12.5A
EV charger (Level 2)240V7,200W30A

Wire Gauge Selection