Understanding Electric Resistance
Electric resistance is a fundamental property of materials that impedes the flow of electric current. The SI unit of electric resistance is the ohm, represented by the symbol "Ω."
Definition of Ohm
- The ohm is defined as the resistance between two points of a conductor when a constant potential difference of one volt applied across the conductor results in a current of one ampere.
- This relationship is described by Ohm's Law, which states: V = I × R, where V is voltage, I is current, and R is resistance.
Importance of Electric Resistance
- Electric resistance is crucial in electrical circuits as it determines how much current will flow for a given voltage.
- It affects the performance of electrical devices, ensuring they operate safely and effectively.
Comparison with Other Units
- Volt (V): The unit of electric potential or voltage. It measures the potential difference that drives the current through a circuit.
- Ampere (A): The unit of electric current. It quantifies the flow of electric charges in a circuit.
- Joule (J): The unit of energy. It represents the amount of work done when a current flows through a resistance.
Conclusion
In summary, the correct answer is option 'C' - ohm, as it is the SI unit that specifically measures electric resistance. Understanding this concept is essential for anyone studying electricity and electronics, especially in fields such as engineering and physics.