What happens to voltage in a series circuit?

• A. Voltage remains constant throughout the circuit
• B. Voltage drop is inversely proportional to resistance
• C. Voltage drop is directly proportional to resistance
• D. Voltage can fluctuate based on current

Answer: (C)

In a series circuit, the voltage drop across each component is directly proportional to its resistance. This relationship is derived from Ohm's Law, which states that voltage (V) is equal to current (I) multiplied by resistance (R). In a series configuration, the same current flows through all components, so the voltage drop across each resistor can be described with the formula V = I × R.

If one component has a higher resistance, it will have a larger voltage drop compared to a component with a lower resistance, assuming the current remains constant. This is why the total voltage supplied by the source is divided among the components in the circuit according to their resistances. Thus, the correct understanding of how voltage operates in a series circuit hinges on recognizing this direct proportionality between voltage drop and resistance.