Electric Current Formula – ElectricalEngineering.XYZ Formulas
Electrical current is a fundamental property associated with circuits. In this post ElectricalEngineering.XYZ presents all the important formulas you should know about Electric current.
Contents
- 1 Electric Current Formula By Definition
- 2 Electric Current Formula from Ohm’s Law
- 3 Electric current Formula when Power and Voltage is Known
- 4 Electric current formula from Power and Resistance
- 5 Electric Current Formula in Single Phase AC Circuits
- 6 Electric Current Formula in Three-Phase AC Circuits
- 7 Other Current Formulas
Electric Current Formula By Definition
By definition electric current is defined as the rate of flow of charge.
1 Ampere is the current in circuit when 1 coulomb of charge passes through a given point in one second.
Mathematically
I = Q/t
where
I = current in amps
Q = charge in coulombs
t = time in seconds
Electric Current Formula from Ohm’s Law
According to Ohm’s law, current is defined as ratio of voltage to resistance.
Mathematically
I = V/R
Where
I = current in amps
V = Voltage in volts
R = Resistance in ohms
Electric current Formula when Power and Voltage is Known
Electric current formula can also be expressed in terms of power and voltage.
I = P/V
Where
I = Current
P = Power
V = Voltage
Electric current formula from Power and Resistance
In case of know power and resistance the electric current formula is:
I = √(P/R)
where
I = Current
P = Power
R = Resistance
Electric Current Formula in Single Phase AC Circuits
In case of single phase AC circuits the current formula is:
I = P/(V * PF)
Where
I = current
P = Power
V = Voltage
PF = Power factor (Cosθ)
Electric Current Formula in Three-Phase AC Circuits
In case of three phase AC circuits the formula for current is:
I = P/(V * PF * 1.73)
Where
I = current
P = Power
V = Voltage
PF = Power factor (Cosθ)