In a series circuit, how are voltages across components related to their resistances?

In a series circuit, how are voltages across components related to their resistances?

• A. The voltages divide in proportion to resistance
• B. They are equal
• C. They depend on current only
• D. They depend on temperature

Answer: (A)

In a series circuit, the same current flows through every component, and the voltage drop across each component is V = I × R. Because the current is the same for all parts, the voltage drop is directly proportional to each component’s resistance. So the voltages divide in proportion to resistance: a higher resistance takes a larger share of the total voltage. The drops add up to the source voltage, forming a voltage divider. For example, if one resistor has twice the resistance of another, it will drop twice as much voltage while the current stays the same. This distribution wouldn’t be equal unless the resistances are equal, and it isn’t determined by temperature alone—temperature can change resistance, but the division of voltage follows the resistances at the given current.

In a series circuit, the same current flows through every component, and the voltage drop across each component is V = I × R. Because the current is the same for all parts, the voltage drop is directly proportional to each component’s resistance. So the voltages divide in proportion to resistance: a higher resistance takes a larger share of the total voltage. The drops add up to the source voltage, forming a voltage divider. For example, if one resistor has twice the resistance of another, it will drop twice as much voltage while the current stays the same. This distribution wouldn’t be equal unless the resistances are equal, and it isn’t determined by temperature alone—temperature can change resistance, but the division of voltage follows the resistances at the given current.