In Ohm's Law, what does the letter 'R' represent?

• A. Region
• B. Resistance
• C. Rate
• D. Return

Answer: (B)

In Ohm's Law, the letter 'R' represents resistance. Resistance is a fundamental concept in electrical theory, indicating how much a material opposes the flow of electric current. It is measured in ohms (Ω) and serves to quantify the opposition given by an electrical component, circuit, or material when a voltage is applied across it.

Ohm's Law states that the relationship between voltage (V), current (I), and resistance (R) can be expressed with the formula: V = I × R. In this equation, if you know the voltage across a component and the current flowing through it, you can calculate its resistance. Understanding resistance is crucial for various applications in circuit design, troubleshooting, and comprehension of electrical systems, making it a vital concept in electrical engineering and related fields.