sec 3 na electronic lesson 1

Basic Electricity and Electronic

Lesson 1

Electronic Systems(Revision)

ProcessInput Output

Input Gather information

Output ‘Action’

Process ‘Brain’. Making decision

Conductor and Insulator(Revision)

• An electrical conductor is a material that allows electricity to flow through easily.

e.g Copper, aluminium, silver, etc

• An electrical insulator is a material that electricity cannot flow through easily.

e.g Wood, plastic, glass, rubber, etc

SemiconductorFoundation of modern electronics

• Midway between electrical conductor and insulator in terms of conductivity.

• Generally, it is made out of Silicon and Germanium

Electrical Terms

VoltageCurrent

ResistancePower

Voltage

• Electrical driving force that drives the electrical current.

• Units: Volts

• Symbol: V (kV)

Current

• Flowing of electrical charge carried by electrons.

• Units: Ampere

• Symbols: A (mA)

Do you know?

• Electric Current Needed to Kill a Human

• http://hypertextbook.com/facts/2000/JackHsu.shtml

Resistance

• The amount of resistivity to the flow of electrical current.

• Units: Ohms

• Symbol: Ω

Water hose illustration

Flow of water(Current)Pressure

(Voltage)

Diameter of hose(Resistance)

Ohm’s Law

IRV

VIP P - Power

Resistors

• The function of the resistor is to protect other components from being damaged by reducing excessively high currents in the circuit.

• The higher the value, the greater the resistance.

Color Code

MultimeterMeasuring resistance

Probes

1. Twist the knob to the ‘Ω’ range of settings. Select a high value such as 200k to start with.

2. Touch the probes on either side of the resistor that you want to test.

3. Record down the value.

Knob

Breadboard

Breadboard allows you to build and test circuits quickly.

Breadboard(Layout)

• http://www.technologystudent.com/elec1/bread1.htm

Resistors in series

21 RRRtotal

Resistors in parallel

21

11RR

Rtotal