Top

Download
PDF

FAQ

×

Sorry!, This page is not available for now to bookmark.

We know that a battery has a positive and a negative terminal. As soon as the voltage is applied to the circuit, pressure or electric tension generates inside it because of some difference called the potential difference.

Now, this pressure pushes the charged electron to move from the negative terminal of the battery to the positive. This movement of electrons from a negative terminal to a positive is what we call the current.

This article discusses the current as of the flow of electrons, and the voltage responsible for pushing the current from one end to the other, and the current voltage difference.

Now, we will discuss the difference of voltage and current:

From the above statement, the voltage was labeled as an electric tension, electric pressure, and the potential difference.

We know that the voltage is generated at the power station. Electrons move randomly inside the circuit, and to give a direction to the electron flow from a negative terminal of a battery to the positive, some push is required; that push is the voltage.

(Image to be added soon)

To understand what voltage is, we will consider an example of a water tank.

Let’s suppose that an empty water tank is placed below the filled tank. Now, as soon as the tap is opened, the water starts flowing out of the upper tank. However, this happens only when pressure is applied to the water in the upper tank.

Similarly, on connecting the circuit to the battery, a difference generates across its ends. The difference coming out from an electric circuit’s power source is called the potential difference/voltage.

The voltage/electric pressure pushes the charged electrons to migrate from the negative end of the battery to the positive side and continues to loop inside the circuit/conducting loop, the flow of electrons produces the current inside the circuit.

Now, these charged electrons or the current do the work in the form of lightning a bulb.

(Image to be added soon)

Thus voltage is the electric tension/pressure that forces the electrons (current) to flow through the circuit that generates electricity, and the bulb glows.

The below table lists the difference between voltage and current:

Now, let’s take another example to understand how voltage and current are related to each other.

Let’s suppose that a water tower is placed standing in a river and it is filled with water. Now, the water tower has enough potential energy to do work. The pump, connected to its right-hand side, and to complete the circuit, a pipe is connected to the left of the tower.

This pump generates pressure on the water tower, which in turn, pushes the water out of the pipe. On increasing the width of the pipe, the potential energy of the tower remains the same, however, the volume of the water flowing out of the pipe increases. Even if we remove the pipe, the potential energy still remains the same.

So, here pressure is the voltage, and water flowing out of the pipe is the current.

This is what we have seen in the remote cells, whether connected to the circuit or left idle, the voltage of the cell remains the same.

V ∝ I

The current flowing through the circuit is directly proportional to the push offered by the circuit to the flow of electrons in a particular direction.

It means the more is the pressure, the more is the water flow or the current flow in the circuit, and vice-versa.

If the potential difference between the two points of the pipe through which water flows is increased, the voltage also increases. It's because the voltage is the potential difference between two points.

FAQ (Frequently Asked Questions)

1. Can the voltage exist without current?

Yes! Voltage can exist without current, while the current cannot flow without voltage. It’s like you want to drive your new car. To drive it (for current flow), you need to start the engine, and without starting it, you cannot move the car even a single-step ahead; this is how voltage pushes the car (current) to move ahead (flow).

2. What is the difference between current and voltage with a real-life example?

Let’s suppose that you didn’t qualify for an entrance exam and are not willing to study for the upcoming exam. All you need is a push to study for the exam. The moment you get it, you start your preparation with full energy. So, the push is the voltage, and preparing with the flow for the exam is the current.

3. Can we control the voltage in a circuit?

Yes!

As per the formula V = IR, we can control the voltage by varying the resistance in the circuit or the conducting loop.

4. How many volts are there in an ampere? What is the safe voltage for a human body?

12 volts are there in 1 ampere. 30 V is the safe voltage for the human body.