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Ohm's Law:
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The fundamental equation to calculate electrical resistance is Ohm's Law, which states that resistance (R) equals voltage (V) divided by current (I). This relationship forms the basis of electrical circuit analysis and design.
The calculator uses Ohm's Law equation:
Where:
Explanation: This equation demonstrates the direct relationship between voltage and current, with resistance acting as the proportionality constant. When voltage increases while resistance remains constant, current increases proportionally.
Details: Accurate resistance calculation is essential for circuit design, component selection, power management, and ensuring electrical safety in various applications from consumer electronics to industrial systems.
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 is Ohm's Law used for?
A: Ohm's Law is used to calculate voltage, current, or resistance in electrical circuits when two of the three values are known.
Q2: What are typical resistance values in circuits?
A: Resistance values range from milliohms in power circuits to megaohms in high-impedance circuits, depending on the application.
Q3: Does temperature affect resistance?
A: Yes, for most conductors, resistance increases with temperature. Some materials like semiconductors show decreased resistance with temperature.
Q4: What is the difference between AC and DC resistance?
A: DC resistance is constant, while AC resistance (impedance) varies with frequency due to inductive and capacitive effects.
Q5: Can Ohm's Law be used for all materials?
A: Ohm's Law applies to ohmic materials where resistance is constant. Non-ohmic materials like diodes and transistors don't follow this linear relationship.