Home
Back
Ohm's Law Formula:
| From: | To: |
Voltage drop across a resistor refers to the amount of electric potential energy lost as current flows through the resistor. According to Ohm's law, this voltage drop is directly proportional to the current flowing through the resistor and its resistance value.
The calculator uses Ohm's law formula:
Where:
Explanation: The formula demonstrates the fundamental relationship in electrical circuits where voltage drop equals the product of current and resistance.
Details: Calculating voltage drop is essential for circuit design, power distribution analysis, component selection, and ensuring proper operation of electrical devices. It helps prevent excessive voltage loss in long wire runs and ensures components receive adequate voltage.
Tips: Enter current in amperes and resistance in ohms. Both values must be positive numbers. The calculator will compute the voltage drop across the resistor in volts.
Q1: Why does voltage drop occur across a resistor?
A: Voltage drop occurs because resistors convert electrical energy into heat energy, resulting in a loss of electric potential as current flows through them.
Q2: How does voltage drop affect circuit performance?
A: Excessive voltage drop can cause devices to malfunction, reduce efficiency, and in power distribution systems, can lead to equipment damage and safety hazards.
Q3: What is the maximum acceptable voltage drop in electrical systems?
A: For branch circuits, the National Electrical Code recommends no more than 3% voltage drop for feeder circuits and no more than 5% for combined feeder and branch circuits.
Q4: Does voltage drop depend on the direction of current flow?
A: No, voltage drop magnitude is the same regardless of current direction, though the polarity reverses with current direction in DC circuits.
Q5: How can I reduce voltage drop in a circuit?
A: Voltage drop can be reduced by using larger conductor sizes, shortening circuit lengths, reducing current draw, or using higher voltage systems.