Calculate Voltage Drop Across Single Resistor

Ohm's Law:

\[ V_{drop} = I \times R \]

Voltage Drop (V_drop):

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1. What is Voltage Drop?

Voltage drop across a resistor refers to the reduction in electrical potential that occurs when current flows through a resistance in an electrical circuit. It represents the energy converted to heat or other forms of energy.

2. How Does the Calculator Work?

The calculator uses Ohm's Law:

\[ V_{drop} = I \times R \]

Where:

\( V_{drop} \) — Voltage drop across the resistor (Volts)
\( I \) — Current flowing through the resistor (Amperes)
\( R \) — Resistance of the resistor (Ohms)

Explanation: Ohm's Law states that the voltage drop across a resistor is directly proportional to the current flowing through it and the resistance value.

3. Importance of Voltage Drop Calculation

Details: Calculating voltage drop is essential for circuit design, power distribution analysis, component selection, and ensuring proper operation of electrical devices. Excessive voltage drop can lead to poor performance and equipment damage.

4. Using the Calculator

Tips: Enter current in amperes (A) and resistance in ohms (Ω). Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between voltage and voltage drop?
A: Voltage is the electrical potential difference between two points, while voltage drop specifically refers to the reduction in voltage across a component due to its resistance.

Q2: Can voltage drop be negative?
A: In standard DC circuits, voltage drop is always positive as it represents energy dissipation. In AC circuits with reactive components, phase angles can create complex voltage relationships.

Q3: How does wire resistance affect voltage drop?
A: All conductors have resistance, so longer wires or smaller gauge wires will cause greater voltage drops, which is important in power distribution systems.

Q4: What is an acceptable voltage drop in electrical systems?
A: For most applications, voltage drop should not exceed 3-5% of the supply voltage to ensure proper equipment operation.

Q5: Does this calculator work for AC circuits?
A: This calculator uses the basic Ohm's Law for resistive loads. For AC circuits with inductive or capacitive loads, impedance calculations are required.