How do you calculate the resistance in a circuit if you know voltage and current?

To calculate the resistance in a circuit when voltage and current are known, you can use Ohm's Law, which states that the voltage (V) across a conductor is directly proportional to the current (I) flowing through it, with the resistance (R) being the constant of proportionality. The formula derived from Ohm's Law is R = E / I, where E represents the voltage.

This means that resistance can be determined by dividing the voltage by the current. The greater the voltage for a given current, the higher the resistance will be. This relationship is fundamental in electrical engineering and helps understand how to manage and design electric circuits effectively.

The other options do not represent the correct relationship articulated by Ohm's Law. For instance, dividing current by voltage or adding current to voltage does not yield resistance, and multiplying them together would provide a value that does not correspond to resistance directly. Understanding this formula is essential for troubleshooting and designing circuits in practical amateur radio and other electronic applications.