What is the resistance of a circuit in which a current of 3 amperes flows when connected to 90 volts?

To find the resistance in this circuit, use the Ohm's Law formula for resistance: R = E / I. Here, the voltage (E) is 90 volts and the current (I) is 3 amperes. Dividing 90 by 3 gives exactly 30, meaning the resistance is 30 ohms. The distractor 270 ohms comes from mistakenly multiplying 90 and 3, which calculates the power in watts, not the resistance. The 1/30 ohm option happens if you accidentally invert the formula and divide current by voltage (I / E).