When a resistor is added in series to a circuit, how is the total resistance affected?

Adding a resistor in series to a circuit increases the total resistance. This is because, in a series circuit, the total resistance is the sum of the individual resistances. Each resistor contributes its resistance value to the total. For example, if you have one resistor with a resistance of 5 ohms and add another resistor with a resistance of 3 ohms in series, the total resistance will be 5 ohms + 3 ohms = 8 ohms.

As a result, the total resistance in the path of the current increases, leading to a decrease in the overall current flow, assuming the voltage remains constant. This principle applies in various electrical applications and is fundamental to understanding how resistors behave in circuits.