Which shortcut calculation is used to approximate the total resistance of a circuit with several identical devices in parallel?

In a circuit where several identical devices are arranged in parallel, the total resistance decreases as more devices are added, making it essential to use the right calculation method for approximation. The correct approach is to find the resistance of one device and then divide that resistance by the number of devices connected in parallel.

This method reflects the principle that in parallel circuits, the overall resistance can be thought of as being shared among the devices. Since each device provides an alternate path for the current, the formula for total resistance (R_total) in parallel circuits for identical resistances (R) is expressed as R_total = R/n, where n is the number of devices.

This means that the total resistance is lower than that of any individual device. Therefore, finding the value of one device and dividing it by the total count of devices gives a good approximation of the total resistance of the circuit.

The other methods listed would not work accurately in calculating total resistance for parallel configurations. For instance, finding the total voltage and dividing by current relates to Ohm's Law and does not directly apply to calculating resistance in parallel setups. Multiplying the resistance of one device by the number of devices suggests that all devices are in series instead of parallel, leading to an incorrect assumption of increasing