Watt's law states that power is the product of current and voltage. How could the power be determined if resistance and current are known?

Watt's law provides a fundamental relationship in electrical engineering that relates power, voltage, current, and resistance. When you know both resistance and current, you can determine power using one of the forms derived from Ohm’s law (V = I × R).

In this case, if you know the current (I) and resistance (R), you can derive the voltage (V) using Ohm’s law as V = I × R. Once you have determined the voltage, you can apply Watt’s law:

Power (P) = Voltage (V) × Current (I).

By substituting the expression for voltage into the power formula, it becomes:

Power (P) = (I × R) × I = I² × R.

This shows that when resistance and current are known, the power can be calculated by taking the current squared and multiplying it by the resistance, confirming that current squared times the resistance is the correct way to determine the power in this scenario. This principle is widely used in electrical calculations and helps engineers design and analyze electrical systems effectively.