Wires: Introduction

The Ethernet cable, which is used to connect your PC to a router, consists of 8 colour-coded wires. Each wire in the cable is protected by an insulating plastic.



Before wireless headphones were invented, wires were used to connect your radio to your headphone. But up to now, wired headphones are still popular. Wires are still necessary in connecting our gadgets.



What are these wires made of?

Semiconductors

The components that make your radio work is made up of semiconductor materials. Semiconductor components has tremendously replaced vacuum tubes. The components that make up your computer's motherboard are also  made up of semiconductors. Examples of these are the integrated circuits and transistors.

What are semiconductors?

Transformers: Introduction

Meralco Transformers

Why are transformers important?
Transformers convert the very high voltage which is 34,500 Volts  from the  electric distribution lines.  The drum-shaped transformer reduces the voltage to a safer 220 Volts. These are  step-down transformers.



 Transformers are also important inside our homes  because some appliances especially the ones that were purchased in the USA requires 110V. The transformer on the left uses a 220V output and has both 110V and 220V output.

Reading The Value Of A Capacitor - Three Digit Number Code

A capacitor with
its capacitance
already indicated

Capacitors like the electrolytic capacitor have their capacitance already indicated like the one on the left. Other capacitors use number codes to indicate their capacitance. The capacitor on the right has a 3 digit number code. 

A capacitor with a 3-digit number code

How do you read these codes?

Resistors: Introduction

The resistor limits the current passing through the circuit. There are fixed resistors and variable resistors



Fixed Resistors


Their resistance can't be changed.
                                     
Carbon Resistors
These resistors are very common in electronic and electrical circuits. Resistors have two fundamental parameters: Resistance in Ohms(Ω) and Power Rating in Watts (W).


The higher the wattage, the bigger the carbon resistor.

Types of Capacitors

Polar Capacitors

They have positive and negative terminals like a battery

Electrolytic capacitors are polar capacitors. 

There are two types of electrolytic capacitor: Radial and Axial.


If connected with exceeding voltage source or wrong polarity, the electrolytic may literally explode because it contains dangerous chemicals.

Capacitors: Introduction

Without capacitors, none of your electronic appliances like the TV and radio would work. Why?
Capacitors can store energy. When the power is cut off, they can function as a temporary battery.

CAPACITORS are devices for storing electric charge. They are also known as CONDENSERS


Capacitance is the ability of the capacitor to store electric charge. 
C is the symbol for capacitance in an equation.
Farad (F) is the unit of Capacitance.
Capacitance values are very small so these are the common units that are generally used.

• Microfarad (μF)
• Nanofarad (nF)
• Picofarad (pF)

Capacitors are important in power supply 
circuits such as the power supply of your computer.