Watts Volts Amps Ohms Calculator

Electrical Power Formulas:

\[ P = V \times I \] \[ V = I \times R \] \[ P = I^2 \times R \] \[ P = \frac{V^2}{R} \]

Voltage (V):

volts (V)

Current (I):

amps (A)

Resistance (R):

ohms (Ω)

Power (P):

watts (W)

Calculated Voltage (V):

Calculated Current (I):

Calculated Resistance (R):

Calculated Power (P):

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1. Ohm's Law and Power Formulas

The fundamental relationships between voltage (V), current (I), resistance (R), and power (P) in electrical circuits are defined by Ohm's Law and the power formulas:

\[ V = I \times R \] \[ P = V \times I \] \[ P = I^2 \times R \] \[ P = \frac{V^2}{R} \]

2. How the Calculator Works

The calculator uses these fundamental relationships to compute any two unknown values when you provide any two known values:

Key Formulas:

If you know voltage and current: \( R = V/I \), \( P = V \times I \)
If you know voltage and resistance: \( I = V/R \), \( P = V^2/R \)
If you know current and resistance: \( V = I \times R \), \( P = I^2 \times R \)

3. Practical Applications

Details: These calculations are essential for circuit design, electrical safety, determining appropriate component ratings, and troubleshooting electrical systems.

4. Using the Calculator

Tips: Enter any two known values (leave the other fields empty) and click Calculate. The calculator will compute the missing values. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is Ohm's Law?
A: Ohm's Law states that the current through a conductor between two points is directly proportional to the voltage across the two points, and inversely proportional to the resistance between them.

Q2: How is power related to these values?
A: Electrical power (in watts) is the product of voltage and current. It can also be calculated from current and resistance or voltage and resistance.

Q3: What units should I use?
A: Use volts (V) for voltage, amps (A) for current, ohms (Ω) for resistance, and watts (W) for power.

Q4: Can I use this for AC circuits?
A: These formulas work for DC circuits and AC circuits with purely resistive loads. For reactive loads (inductors, capacitors), you need to consider impedance and power factor.

Q5: Why can't I enter all four values?
A: The calculator is designed to compute missing values from known values. If you enter all four, there would be nothing to calculate and the system would check for consistency.