If a circuit containing five 50 ohm resistors has a total resistance of 10 ohms, the circuit is a:

In a series-parallel circuit, some components are arranged in series while others are arranged in parallel. In this scenario, having five 50-ohm resistors yielding a total resistance of 10 ohms suggests that the configuration of the resistors includes both series and parallel elements.

When resistors are connected in series, their resistances add up. Conversely, when resistors are connected in parallel, the total resistance can be calculated using the formula ( \frac{1}{R_{total}} = \frac{1}{R_1} + \frac{1}{R_2} + \ldots + \frac{1}{R_n} ).

For five 50-ohm resistors arranged in a certain way to achieve a lower total resistance of 10 ohms, some must be placed in parallel. This is because if all five were in series, the total resistance would be 250 ohms (50 ohms each added together). Therefore, to achieve a total of 10 ohms, at least some of the resistors need to be connected in parallel to lower the total resistance effectively.

In summary, the presence of both series and parallel configurations is what confirms that the circuit is a series-parallel