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Ohm's Law Equation:
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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 the 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 systems, 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.
Q1: Can I use this for AC circuits?
A: This calculator works for DC circuits. For AC circuits, you need to consider impedance which includes resistance, capacitance, and inductance.
Q2: What if I know resistance and voltage but need current?
A: You can rearrange Ohm's Law: \( I = V/R \). Similarly, \( V = I \times R \) if you need voltage.
Q3: What are typical resistance values?
A: Resistance varies widely - from milliohms in wires to megaohms in insulators. Common resistors range from 1 ohm to 10 megaohms.
Q4: Why does resistance matter in circuit design?
A: Resistance determines how much current flows for a given voltage, affects power dissipation (\( P = I^2R \)), and influences voltage drops in circuits.
Q5: What affects a material's resistance?
A: Resistance depends on the material's resistivity, length, cross-sectional area, and temperature (for most conductors, resistance increases with temperature).