1. What is Ohm's Law?

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.

Where:

• \( V \) — Voltage (volts, V)
• \( I \) — Current (amperes, A)
• \( R \) — Resistance (ohms, Ω)

2. Power Formulas

Electrical power can be calculated using several formulas derived from Ohm's Law:

Where \( P \) is power in watts (W).

3. How the Calculator Works

The calculator uses the relationships between voltage, current, resistance, and power to calculate any one variable when the other two are known. It automatically selects the appropriate formula based on what you're trying to calculate and the inputs provided.

4. Using the Calculator

Steps:

1. Select what you want to calculate (Power, Voltage, Current, or Resistance)
2. Enter the two known values (the input field for what you're calculating will be hidden)
3. Click "Calculate" to get the result

5. Frequently Asked Questions (FAQ)

Q1: What units should I use?
A: Use volts (V) for voltage, amperes (A) for current, ohms (Ω) for resistance, and watts (W) for power.

Q2: Can I calculate power if I only know voltage and resistance?
A: Yes, the calculator will use \( P = V^2 / R \) in this case.

Q3: Is this calculator accurate for AC circuits?
A: This calculator is designed for DC circuits. For AC circuits, you need to consider power factor and other AC-specific parameters.

Q4: What if I get a negative value?
A: The calculator only accepts positive values as these quantities are always positive in real-world applications.

Q5: How precise are the calculations?
A: Results are rounded to 2 decimal places for clarity, but the underlying calculations use full precision.