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Ohm's Law:
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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. It is a fundamental principle in electrical engineering and physics.
The calculator uses Ohm's Law equation:
Where:
Explanation: The equation shows that resistance equals voltage divided by current. Higher voltage with the same current means higher resistance, while higher current with the same voltage means lower resistance.
Details: Calculating resistance is essential for designing electrical circuits, selecting appropriate components, troubleshooting electrical problems, and ensuring safe operation of electrical devices.
Tips: Enter voltage in volts and current in amps. Both values must be positive numbers. The calculator will compute the resistance in ohms (Ω).
Q1: What are typical resistance values in circuits?
A: Resistance values vary widely from milliohms in power systems to megaohms in sensitive electronics, depending on the application.
Q2: Does Ohm's Law apply to all materials?
A: Ohm's Law applies to "ohmic" materials where resistance is constant. Some materials like diodes are non-ohmic and don't follow this linear relationship.
Q3: How does temperature affect resistance?
A: For most conductors, resistance increases with temperature. For semiconductors, resistance typically decreases with temperature.
Q4: What's the difference between resistance and impedance?
A: Resistance applies to DC circuits, while impedance is the AC equivalent that includes both resistance and reactance.
Q5: How can I measure resistance directly?
A: You can use a multimeter set to resistance mode, but the circuit must be powered off and isolated for accurate measurement.