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Ohm's Law Formula:
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Ohm's Law is a fundamental principle in electrical engineering and physics that describes the relationship between voltage, current, and resistance in an electrical circuit. It states that the current through a conductor between two points is directly proportional to the voltage across the two points.
The calculator uses Ohm's Law formula:
Where:
Explanation: The formula shows that resistance equals voltage divided by current. This relationship is linear for ohmic conductors where resistance remains constant regardless of voltage or current.
Details: Calculating resistance is crucial for circuit design, troubleshooting electrical systems, selecting appropriate components, and ensuring electrical safety in various applications from household wiring to complex electronic devices.
Tips: Enter voltage in volts and current in amperes. Both values must be positive numbers greater than zero. The calculator will compute the resistance in ohms.
Q1: What are the units for resistance, voltage, and current?
A: Resistance is measured in ohms (Ω), voltage in volts (V), and current in amperes (A).
Q2: Does Ohm's Law apply to all materials?
A: No, Ohm's Law applies primarily to ohmic conductors where resistance remains constant. Non-ohmic materials like diodes and transistors don't follow this linear relationship.
Q3: What is the typical resistance range for common materials?
A: Conductors have low resistance (0.1-10Ω), semiconductors have moderate resistance, and insulators have very high resistance (millions of ohms).
Q4: How does temperature affect resistance?
A: For most conductors, resistance increases with temperature. For semiconductors, resistance typically decreases with temperature.
Q5: Can I use this calculator for AC circuits?
A: This calculator works for DC circuits and AC circuits with purely resistive loads. For reactive components, impedance calculations are needed.