Contents: Voltage Simple Definition
What Is Voltage in Simple Terms?
Before you can understand what voltage is, please make sure you read my very short, easy-to-read article: What Is an Electric Circuit?
And you might want to read What Is Electric Current? too. It doesn’t take long to read and it will REALLY help you in understanding the bare-bone basics of what voltage is.
As we’ve discussed in previous posts, electricity is caused by the movement of electrons in an electrical circuit. That movement across the circuit is what we call an electric current.
But the electrons need something to push them along the circuit for it to create an electric current.
The electrical push/pressure that causes the current to flow in a circuit is called voltage.
The greater the voltage, the greater the current (flow of electrons) through an electrical conductor (like a wire).
So, in other words,
voltage just measures how strongly electricity is being pushed from a power source (like a battery or wall outlet) through a circuit.
Voltage is measured in Volts (V).
Voltage vs Current (The Straw Analogy)
Voltage and current are very closely related because you cannot have any current flowing without having voltage pushing it.
Think of someone blowing air through a drinking straw. The air current that’s going through the straw is like the electric current that flows through a wire. And the person who’s blowing the air and pushing the air through the straw (putting pressure on the air so it starts moving) is like voltage.
The voltage could be compared to the person’s diaphragm. It’s the thing that starts the air moving by putting pressure on the person’s lungs. Just like the voltage from a battery is the thing that starts the electrical current to move through the wires.
Without the person blowing the air, there is no air current. Without voltage pushing the electrons, there is no electrical current.
Voltage vs Potential Difference
To continue with the example above, whether the person is blowing air through the drinking straw or not, the potential of that person’s ability to blow air is always there.
The same goes for voltage. The voltage is always there in a battery. The battery has the potential to move electrons through wires whether or not it’s being used, just like the person has the potential to blow air through the straw whether or not they’re actually blowing air through a straw.
So when discussing voltage, you’ll often hear the term potential difference or electric potential difference.
Voltage and potential difference are often used interchangeably because they’re describing the same thing.
Volts (12-volts, 24-volts, 48-volts) specify how much potential a battery (or another power source) has to push electrons through a circuit. The greater the voltage, the more potential it has to push more electrons.
For example, an AA alkaline battery (which almost everyone has in their house) is 1.5 volts (or 1.5 V). But a typical electrical outlet in your house (if you’re in the United States or Canada) is 120 volts (or 120 V). The electrical outlet has more potential to push more electrons than the AA battery.
Volts & Appliances/Devices
Knowing the voltage of a power source (like a battery or a regular wall outlet) can tell you what appliances/devices you can hook up to it.
For example, if you have a 12-volt kettle, you could hook it up to a 12-volt battery/solar system. And, if you have a regular 120-volt lamp and a 120-volt electrical outlet, you can connect those two together as well.
I usually like to think of voltage as a way to understand the compatibility between a power source (like a battery or an outlet) and appliances/devices.
Conclusion: What Is Voltage in Simple Words?
Voltage is one of the most fundamental concepts in electricity. Simply put,
voltage is the pressure that pushes electricity through a circuit and it’s measured in volts (V).
Voltage is an important concept because it determines how much power an electric device needs.
In order for an electronic device to work, there must be a power source (like a battery or electrical outlet) and that power source needs to provide a voltage. The voltage will determine how much current flows through the device.
Without voltage, we would be living in a world without cell phones, computers, or televisions. It is also responsible for powering the electrical grid that provides our homes and businesses with electricity.