# Calculate the Power Consumed by a Light Bulb

## How can we calculate the power consumed by a light bulb?

A light bulb consumes (4.0 W) of power when (4.0 V) voltage is applied to it. What is the resistance of the light bulb, assuming that the bulb's resistance does not change?

## Calculating the Power Consumed by a Light Bulb

To calculate the power consumed by a light bulb, we use the formula P = V²/R, where P is power, V is voltage, and R is resistance.

When a light bulb uses 4.0 W of power and a voltage of 4.0 V, we can determine the resistance of the light bulb by rearranging the formula to solve for R. By substituting the given values into the equation, we find that the resistance of the light bulb is 4.0 Ohm.

Ohm's law is a fundamental principle in understanding the relationship between power, voltage, and resistance in electrical circuits. By applying this law, we can calculate various electrical properties and ensure the efficient operation of devices.

Understanding how to calculate the power consumed by a light bulb allows us to make informed decisions about energy consumption and efficiency. By utilizing the principles of Ohm's law, we can optimize electrical systems for improved performance and sustainability.