# Electronic basics: your first circuit

One of the simplest circuits that work correctly that we can build is the circuit that lights up the LED.

We will use 9V battery, 470 ohm resistor and LED.

We will discuss resistors and LEDs in more detail later, but now let's create the first circuit.

If you don’t need it, you don’t need to buy any gears or components, but I strongly recommend that you buy and buy a starter kit called "ELEGOO UNO R3 Project Most Complete Starter Kit" from Elegoo. You can find it on Amazon.

Tinkercad from Autodesk, the famous creator of AutoCAD, allows you to create and simulate not only electronic circuits, but also electronic circuits-you can also create designs for 3D printing. This is a very cool web application.

Click onCreate a new circuitButton, you will see the circuit builder interface:

Now you can drag and drop components in the right sidebar of the main screen.

Choose a 9VVoltageBattery, resistor and LED:

Now, hovering your mouse over each item will show you the connections you can create from or with them. For example, a battery has a positive electrode and a negative electrode:

Drag the negative pole to one of the resistors:

Now, connect the resistor to the cathode on the left called the LED, the cathode is straight.

Finally, connect the anode (the right pin of the LED) to the anode of the battery:

You can click on them to change the color of the wires:

You can change the settings of each component with a single click. For example, click on the resistance to find and change itsRevoltValue, the default is 1kΩ:

Double-click the wire to add a point on it, so you can make a better circuit:

After sorting it out, the results are as follows:

Click nowStart simulationButton. You will see the LED light up until you clickStop simulation:

Now try to change the resistance to 220Ω:

Run the simulation again and you will see a warning on the LED to notify youcurrentIf there is too much flow, the recommended maximum current that the LED can handle is 20mA:

You can also change the value of the resistor while the simulation is running. If you write 1000Ω instead of 220Ω, you will see a decrease in the brightness of the LED.

Add 10000Ω and the LED will now show no light at all.

The higher the resistance of the resistor, the less current flows in the circuit, so the LED consumes less current, thus showing bright light.

Remember Ohm's Law`I = V / R`: The current flowing through the circuit has`220Ω`The resistance is 9/220 =`40mA`.

use`1kΩ`Resistance current91000=`9mA`.

This is the same circuit, but in the real world: