Amps, volts, watts — there are many different ways to measure electricity. And using only one measurement doesn't tell the whole story. But using a combination of amps, volts and watts can help us better understand the situation. So, what do these terms mean and how do they work together?
- Current is the rate of flow of an electric charge and is measured in amps.
- Voltage is the force of the electricity.
- Power is the amount of electricity being used at any given moment. It's measured in watts, or kilowatts on a larger scale.
The water hose analogy
We'll use the water hose analogy to demonstrate how they all work together. Imagine that the water is electricity flowing through a hose.
- The current would be the diameter of the hose the water flows through.
- The voltage would be the water pressure.
- The power (in watts) is the amount of water coming out of the pipe at any given moment.
How it all flows together
These measures are all interconnected — if you change one, then either one or both of the others will also change. That also means that if you know any two of these measurements, you can easily figure out the third.
- Power is current multiplied by the voltage (Watts = Amps x Volts)
- Voltage is power divided by current (Volts = Watts / Amps)
- Current is power divided by voltage (Amps = Watts / Volts)
Measuring energy use
Going one step further, imagine that the water is going from the hose into a pool. The water in the pool represents the total energy used. Energy is the amount of power used over time and can be measured in kilowatt-hours (kWh), which is often the measurement that appears on an electric bill.
- The amount of energy used is power multiplied by time (kWh = Watts x Time)
- Power is energy divided by time (Watts = kWh / Time)
Understanding how the different measures of electricity work together to form a bigger picture can help you make knowledgeable decisions when it comes to electricity.