Understanding Voltage
What is Voltage?
Voltage is one of the most important concepts in electricity.
In simple words, voltage is the electrical push that helps electric charges move through a circuit.
The difference in electrical potential between two points is called potential difference or voltage.
Voltage: A Water Tank Example
Let us understand voltage with a simple example.
Imagine two water tanks connected to a pipe.
- Tank A is placed at a greater height.
- Tank B is placed at a lower height.
When the tanks are connected, water tends to flow from the higher tank towards the lower tank.
Why?
Because there is a difference in water level (height) between the two tanks.
How is this similar to electricity?
Similarly, in an electrical circuit, when there is a difference in electrical potential between two points, electric charges can move through a conducting path.
The Comparison
| Water System | Electrical System |
|---|---|
| Difference in water level | Potential difference |
| Water pressure helps water flow | Voltage provides electrical push |
| Flow of water | Flow of electric charge |
| Water flow rate | Electric current |
So, we can think of voltage as the electrical equivalent of the difference in water level or pressure that drives flow.
Voltage and Current
Voltage and current are related, but they are not the same.
- Voltage → Provides the push.
- Current → Flow of electric charge.
For example, a battery provides a potential difference (voltage). When a conducting path is completed, this potential difference can drive electric current through the circuit.
Formula of Voltage
Potential difference is defined as the work done per unit charge:
Where:
- V = Potential difference (Voltage)
- W = Work done
- Q = Electric charge
Unit of Voltage
The SI unit of voltage is volt (V).
This means 1 volt is the potential difference when 1 joule of work is done to move 1 coulomb of charge.
An Easy Way to Remember
Difference in water level → Water flows
Difference in electric potential → Electric charge can flow
Voltage is the potential difference that provides the driving force for the movement of electric charge.
Voltage = Electrical Push
Current = Flow of Charge
