What equation would you use to determine resistance if voltage and current are known?

• A. R = E/I
• B. R = I/E
• C. R = E x I
• D. R = I x E

Answer: (A)

To determine resistance when voltage and current are known, Ohm's Law is applied, which states that the resistance ( R ) is equal to the voltage ( E ) divided by the current ( I ). This relationship can be expressed with the formula ( R = E/I ). This equation helps to understand how resistance opposes the flow of electric current in a circuit when a certain voltage is applied.

When voltage is measured in volts and current in amperes, this calculation allows you to quantify how much the current is impeded by the material or the circuit's configuration. The correct formulation ensures you can accurately assess the resistance based on the observed voltage and current values, which is crucial for troubleshooting and designing electrical systems.