How do you calculate the power consumed by a resistor?

To determine the power consumed by a resistor, the formula P = V^2 / R is indeed correct. This equation is derived from Ohm's Law, which states that the voltage across a resistor (V) is equal to the current (I) flowing through it multiplied by the resistance (R), or V = I × R.

When calculating power, we have several relationships that can be expressed based on Ohm’s Law. The power consumed by an electrical component is generally calculated using the relationship P = V × I. By substituting Ohm's Law into this equation, we can express power in terms of voltage and resistance.

Using V = I × R allows us to isolate current (I) as I = V / R. By substituting this into the power formula P = V × I, we get P = V × (V / R), which simplifies to P = V^2 / R. This shows how the power is dependent on the voltage across the resistor and the resistance itself.

This formula highlights how power increases with the square of the voltage and inversely with the resistance, indicating that for a given resistor, increases in voltage lead to a much larger increase in power consumption.

This relationship is crucial in