What does Ohm's Law express about the relationship between voltage, current, and resistance?

• A. V = I / R
• B. V = I + R
• C. V = I * R
• D. V = I - R

Answer: (C)

Ohm's Law clearly expresses the fundamental relationship between voltage, current, and resistance in an electrical circuit. According to this law, the voltage (V) across a conductor is directly proportional to the current (I) flowing through it, provided the temperature remains constant, and it can be withstanded due to the resistance (R) of the conductor. The correct equation is V = I * R, meaning that voltage is equal to the product of current and resistance.

In practical terms, this means that if you know the current flowing through a resistor and the resistance of that resistor, you can easily calculate the voltage across it. For example, if you have a circuit with a current of 2 amperes flowing through a resistor of 5 ohms, you can use Ohm's law to find the voltage: V = I * R, which would equal 10 volts.

This relationship is vital for understanding how electric circuits operate and designing them effectively, as it allows engineers to determine how voltage, current, and resistance affect the performance of electrical systems.