In a series circuit, does the voltage across each component stay the same?

In a series circuit, does the voltage across each component stay the same?

• A. It doubles with each component.
• B. Yes, it is the same for all components.
• C. It is zero for all but one.
• D. No, it varies with resistance.

Answer: (D)

In a series circuit, the current is the same through every component, but the voltage across each component depends on its resistance. Using Ohm’s law, V = I × R, the same current times a larger resistance gives a larger voltage drop, while a smaller resistance gives a smaller drop. The total supply voltage is the sum of all these drops, so the voltage across components in series is not identical; it varies according to how much resistance each component has. If all resistances were equal, the drops would be equal, but with different resistances they won’t be.

In a series circuit, the current is the same through every component, but the voltage across each component depends on its resistance. Using Ohm’s law, V = I × R, the same current times a larger resistance gives a larger voltage drop, while a smaller resistance gives a smaller drop. The total supply voltage is the sum of all these drops, so the voltage across components in series is not identical; it varies according to how much resistance each component has. If all resistances were equal, the drops would be equal, but with different resistances they won’t be.