Medical College Admission Test (MCAT) Practice Exam 2025 – The Complete All-in-One Guide for Exam Success!

In a series circuit, the total resistance is the sum of the individual resistances. When additional resistors are added, the total resistance of the circuit increases. According to Ohm's Law, which states that the voltage across a circuit is equal to the current through the circuit multiplied by the resistance (V = IR), if the total resistance increases while the current remains constant, the voltage across the entire circuit must also increase in order to maintain that relationship.

However, if you look at a specific resistor within the circuit, the voltage drop across that particular resistor increases as its resistance increases. Therefore, while the total voltage provided by the source remains constant, the individual voltage drops across the resistors can vary depending on their resistance values.

In summary, as additional resistors are added to a series circuit, the total resistance increases, and for a fixed current scenario, the overall behavior leads to adjustments in the voltage drops across each resistor, influencing how voltage is distributed throughout the circuit. This foundational concept highlights how voltage and resistance relate in a series circuit as more resistors are introduced.