What is the difference between amps volts and watts

An appliance that uses a large amount of current, such as an electric stove, may need to be on a separate circuit with a higher voltage. This is because it requires a higher wattage, meaning that it uses up more current per unit of time than other appliances, so it needs more voltage.

Without the higher voltage, it wouldn't run, because it would be starved for the current it needed to be able to operate. Understanding the relationship between various electrical terms can also help consumers evaluate monthly power bills. Electrical consumption is measured in watts, or watt-hours, and power companies measure and bill consumption in kilowatt-hours, which is the equivalent of using watts of power for one hour. Many households use hundreds of kilowatt-hours each month.

The number of kilowatts billed to each household is connected to volts and amps. Volts remain constant, but amps change based on the demand for current. When people switch on more appliances or run them for longer periods, they increase the demand for current, which in turn increases total watts consumed. The resistance in electrical wires consumes power, and the power consumed increases as the current going through the wires increases.

You can see how this happens by doing a little rearranging of the two equations. What you need is an equation for power in terms of resistance and current. Let's rearrange the first equation:. What this equation tells you is that the power consumed by the wires increases if the resistance of the wires increases for instance, if the wires get smaller or are made of a less conductive material.

But it increases dramatically if the current going through the wires increases. So, using a higher voltage to reduce the current can make electrical systems more efficient. The efficiency of electric motors also improves at higher voltages. This improvement in efficiency is what drove the automobile industry to consider switching from volt electrical systems to volt systems in the s.

As more cars shipped with electric-powered amenities — video displays, seat heaters, "smart" climate control — they required thick bundles of wiring to supply enough current.

Switching to a higher-voltage system would provide more power with thinner-gauge wiring. The switch never happened , because carmakers were able to boost efficiencies with digital technology and more efficient electric pumps at 12 volts. But some new models employ hybrid systems with a separate volt generator to power advanced features like idle shut-off while increasing overall system efficiency.

Sign up for our Newsletter! Mobile Newsletter banner close. Mobile Newsletter chat close. Mobile Newsletter chat dots. Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe. In most electrical systems, the conductor is a wire. The ampere , or amp for short, is the unit of measure for electrical current.

In our water analogy, electrical current is equivalent to the flow rate or amount of water flowing through the hose. Voltage is the difference in electrical potential, or the number of electrons, between any two points in an electrical circuit. In our water analogy, voltage is equivalent to water pressure. Pressure is the force that moves the water through the hose, just like voltage pushes electrons through a conductor.

Resistance tries to slow down the flow of electrons. In our water analogy, resistance is the diameter of the hose. A wide hose has very little resistance and allows water to flow through it quickly. Conductors with low electrical resistance, like copper wire, allow electrons to flow easily through them, just like the wide hose.

Power is the rate at which electrical energy is transferred in a circuit and is measured in watts. Power is a little harder to explain using the water analogy. In an electrical system, you can increase the power by increasing the current or increasing the voltage. It is represented by a simple equation.

If you keep the resistance the same and increase the voltage, the current has to increase. Like in our hose analogy, if you increase the pressure, then more water will flow through it. Resistance works against voltage to slow down the flow of electrons.