Enter 2 values to get the other values and press the Calculate button:
I
→
┌─────────┐
│ + R │
│V ≡≡≡ ≈≈≈│
│ - │
└─────────┘
Let's calculate the missing values for a simple DC circuit:
Given:
Calculations:
Current: I = V ÷ R = 12V ÷ 4Ω = 3 amps
Power: P = V × I = 12V × 3A = 36 watts
💡 Try it: Enter 12 in Voltage and 4 in Resistance, then click Calculate to see this example in action!
The voltage V in volts (V) is equal to the current I in amps (A) times the impedance Z in ohms (Ω):
The complex power S in volt-amps (VA) is equal to the voltage V in volts (V) times the current I in amps (A):
The real power P in watts (W) is equal to the voltage V in volts (V) times current I in amps (A) times the power factor (cos φ):
The reactive power Q in volt-amps reactive (VAR) is equal to the voltage V in volts (V) times the current I in amps (A) time the sine of the complex power phase angle (φ):
The power factor (PF) is equal to the absolute value of the cosine of the complex power phase angle (φ):
Given:
Results:
Try entering these values in the calculator above to see the calculations!
Enter 2 values to get the other values and press the Calculate button:
The average power P in watts (W) is equal to the energy consumed E in joules (J) divided by time period Δt in seconds (s):
Problem: A light bulb consumes 7200 J of energy over a period of 60 seconds. What is the average power consumption?
Given: Energy (E) = 7200 J, Time period (Δt) = 60 s
Solution: P = E / Δt = 7200 J / 60 s = 120 W
Answer: The average power consumption is 120 watts.
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