The Rectifier Diode

Diode allows current to flow in one direction only. It looks a lot like a resistor, as you can see


These diodes can protect parts of the circuit against reverse current flow, but there is a priceto pay: diodes also cause a drop in the voltage of around 0.7 V. The 1N4004diode is rated to handle 1 A and 400 V, much higher than we will be using.It’s a tough, common, and low-cost diode.

The capacitor

A capacitor is a device that holds an electric charge. It consists of two metal plates with an insulating layer that allows an electric charge to build up between the plates. Once the current is stopped, the charge remains and can flow out of the capacitor (called discharging the capacitor) .

The amount of charge that a capacitor can store is measured in farads, and one farad is actually a very large amount. Therefore, you will generally find capacitors with values measured in picofarads or microfarads

Reading Capacitor Value


The first two digits represent the value in picofarads, and the third digit is the multiplier in tens. For example, the capacitor shown in Figure 4-12 is labeled 104. This equates to 10, followed by four zeros, which equals100,000 picofarads/pF .

Types of Capacitors

Our projects will use two types of capacitors: ceramic and electrolytic.

Ceramic Capacitors

Ceramic capacitors, such as the one shown below , are very small and therefore hold a small amount of charge. They are not polarized and can be used for current flowing in either direction. The schematic symbol for a nonpolarized capacitor is shown in Figure 4-13. Ceramic capacitors work beautifully in high-frequency circuits because they can charge and discharge very quickly due to their small capacitance.


nonpolarized: U can connect the component in any direction/orientation ,no positive and negative terminal.

Electrolytic Capacitors

They are bigger than ceramic capicator hence can store large and have large capacitance , A mark ing on the cover shows either the positive (+) side or negative side (–).you can see the stripe and the small negative (–) symbol thatidentifies the negative side. Like resistors, capacitors also have a level of tolerance with their values.


Electrolytic capacitors are often used to make smooth power supply voltages.

Push button:

As the name satates when we push the button it allows to pass the current .


Notice how the button at the bottom of the figure is inserted into the breadboard, bridging rows 23 and 25. When the button is pressed, it connects the two rows. The schematic symbol for this particular push button is shown above  The symbol represents the two sides of the button, which are numbered with the prefix S. When the button is pressed, the line bridges the two halves and allows voltage or current through.

piezoelectric Buzzers ( make some noise………….)

A piezoelectric element (piezo for short), or buzzer, is a small, round device that can be used to generate loud and annoying

noises that are perfect for alarms—or for having fun.


When alternating current is applied (such as on . . . off . . . on . . . off). the plate vibrates and generates sound waves.It’s simple to use piezos with Arduino. The piezo elements are not polarize.

i have attach the pdf of basic electronic component. we will study some more components later…..

About electricity



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s