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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's 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 amperes. Both values must be positive numbers. The calculator will compute the resistance in ohms.
Q1: What if I know resistance and voltage but need current?
A: You can rearrange the formula: \( I = V / R \). This calculator focuses on finding resistance, but other versions can calculate current or voltage.
Q2: Does Ohm's Law apply to all materials?
A: Ohm's Law applies to "ohmic" materials where resistance is constant. Some materials (like semiconductors) are non-ohmic and don't follow this linear relationship.
Q3: What are typical resistance values in circuits?
A: Resistors range from fractions of an ohm to millions of ohms, depending on application. Common values are between 100Ω and 100kΩ for many electronic circuits.
Q4: How does temperature affect resistance?
A: For most conductors, resistance increases with temperature. The relationship is described by the temperature coefficient of resistance.
Q5: What's the difference between resistance and impedance?
A: Resistance applies to DC circuits, while impedance (which includes resistance and reactance) applies to AC circuits with capacitors and inductors.