In a series circuit, how does the voltage drop distribute across resistors?

• A. It is the same for all resistors
• B. It is random and not related to resistance
• C. It does not depend on current
• D. Voltage divides proportionally to each resistor's value

Answer: (D)

In a series circuit, the same current flows through every resistor, so the voltage drop across each resistor depends on its resistance. By Ohm’s law, V = I × R, so each drop is V_i = I × R_i. Since the current is the same for all components, a larger resistance yields a larger voltage drop. The total supply voltage equals the sum of all drops, meaning the voltage is divided among the resistors in proportion to their values. For example, with two resistors of 2 Ω and 4 Ω carrying the same current, the drops are 2I and 4I, so the 4 Ω resistor takes twice as much of the total voltage as the 2 Ω resistor. If the resistors were equal, they'd share the voltage equally.