sec 3 na electronic lesson 1
TRANSCRIPT
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