Electronics Quiz Flashcards
What are the classifications of matter? (3)
Chemical
Physical
Electrical
Chemical matter is broken down into what two groups?
Simple - atom
Complex - molecule
Physical matter is broken down into what three groups?
Solid
Liquid
Gas
Electrical matter is broken down into what three groups?
Conduction
Insulation
Semi-conduction
Explain the composition of an atom including the polarity of each item?
Protons (pos)
Electrons (neg)
Neutrons (neut)
Define simple matter
composed of one earth element
Define complex matter
Two or more elements
Give three examples of Insulators
Glass
Mica
Rubber
Give three examples of conductors
Gold
Silver
Copper
Give two examples of semi-conductors
Silicon
Germanium
What are the shell levels of an atom called and how many electrons in each?
K - 2
L - 8
M - 18
N - 32
What is the outer shell called?
Valence shell
Explain what effects the electrical stability of an atom?
distance of the valence shell from the core - closer the more stable
Semi-conductors have _______ valence electrons
4
What is covalent bonding?
When electrons in the valence shell share 2 or more atoms
A bond of silicone atoms forming a silicone crystal is said to be _________ material
instrinsic
Explain the term doping
mixing intrinsic and extrinsic material
Conduction in a pure crystal can only be achieved by exceeding certain levels of _________ and _________
heat and light
What type of materials are added to semi-conductor material to form P type material? (4)
Gallium
Aluminum
Indium
Boron
What type of materials are added to semi-conductor material to form N type material?
Phosphorus
Antimoni
Arsenic
What are the majority carriers in P type material?
Holes
What are the majority carriers in N type material?
electrons
Explain what is meant by the term conventional flow?
Electron flow positive to negative
Explain what is meant by the term electron flow?
electron flow negative to positive
What happens when a piece of N type semi-conductor material and a piece of P type semi-conductor material are joined?
Combines until a depletion region is formed
What is the material that joins n type and p type called?
junction diode
How is the depletion region overcome?
applying knee voltage
What is the barrier potential for silicon and germanium semi-conductor material are joined?
Silicon = .7v
Germanium = .3v
Explain what is meant by saying a diode is forward bias?
Diode is conducting
Explain what is meant by saying a diode is reverse bias?
diode is not conducting
What is VBR?
Voltage breakdown reverse is the point at which most diodes will be destroyed
What does VK mean?
knee voltage
What is the purpose of a power supply?
To provide a constant dc voltage to circuits
What are the 4 major components that make up a power supply?
transformers
rectifiers
filters
regulators
What are the components used in a power supply filter and why do they improve the output? (3)
capacitors
inductors
resistors
What will determine the type of filter used?
Requirements of the load
What is the purpose of a voltage regulator?
provide constant voltage to the load
How does a zenner diode differ from a junction diode?
designed to operate in reverse bias
What are the two types of breakdown associated with a zenner? What are their voltage ranges?
Zenner - 0 to 6v
Avalanche - 6v and greater
The majority of zenner’s operate on __________ breakdown
avalanche
What factor will decide the voltage rating of a zenner diode?
doping
What are three applications of a zenner diode?
voltage regulation
peak limiter
overload protection
What is an LED and how does it operate?
light emitting diode
What is a photo diode and how does it operate?
light deception that goes f.b when exposed to light
What is a triac and how does it operate?
3 terminal bi-direction device used to control ac power
What is a diac and how does it operate?
It is a bi-directional device with no gate used as a triggering device for triacs
What is an optocoupler?
Isolation device that consists of an LED and a photodiode functions like a coil and contact
What is thermistor?
thermal sensitive resistor
Explain the term RTD and give an example?
Resistive temp device
What types of input signals are used in electronic control systems? (2)
Analog
Digital
Explain proportion control?
Varying response to input signal
Explain proportion-integral control?
adjusted response to input signal - tries to correct response to match s.p
What is a transducer?
device that converts a signal from one type to another
What forces keep electrons in their orbit? (2)
Magnetic
Kinetic
Why is an atom considered to be in a neutral state when it is by itself?
same # of electrons and protons
