Electronics Basics: Current

Current is the flow of electrons between two points with different voltage.

It is measured in ampere (A).

We have 2 types of current: alternating current (AC) and direct current (DC)

Anyone listens to AC/DC?

In direct current (DC) the current flows in one direction, and it’s the type of current generated by batteries.

In alternating current (AC) the current periodically changes direction, and it’s the current provided by the grid that we connect to in our houses, where we add sockets into our walls.

Those two different types of current have very different characteristics, and they allow very different usages and applications.

For example, DC is not good for long distance transmission of current. We use AC instead.

Most electronic devices run with DC.

That’s why we use rectifier that allow us to transform AC into DC.

We can also do the opposite, using devices called power inverters, used often in recreational vehicles for example.

Lessons in this unit:

0: Introduction
1: Introduction to Electronics
2: Analog vs digital
3: ▶︎ Current
4: Voltage
5: Vcc, ground, ...
6: Resistance
7: Short Circuit
8: Your first circuit
9: Prototyping using breadboards
10: Using a multimeter
11: Measuring voltage, current and resistance using a multimeter
12: Milli Micro Nano Pico
13: Calculating Ah from Watts
14: Electronic Project: Build a voltage divider
15: Electronic Project: Build a LED dimmer with a potentiometer

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