Quiz 1 Flashcards
What is matter?
Any substance that has mass and takes up space
Who discovered the electron? When?
JJ Thomas, 1897
What is an element?
The base units that all matter is made up of
How many elements are there?
109
What is an atom?
The smallest single unit of an element that retains that element’s characteristics
What is a compound?
A substance that is comprised of two or more atoms; which are chemically combined.
What is a molecule?
The smallest single unit of a compound that retains that compounds characteristics.
What three subatomic parts are atoms made up of?
Protons, neutrons, electrons.
What charge do electrons have and where are they located?
Orbiting the nucleus, negative charge.
Where are protons located and what charge do they have?
Located in the nucleus and are positively charged
Where are neutrons located and what charge do they have?
Located in the nucleus, neutral charge.
What is the difference between each element?
The number of protons they have
What gives the atomic number and characteristics of an element?
The number of protons it has
How many electrons can fit in the first shell about the nucleus?
2 electrons
How many electrons can fit in the second shell around the nucleus?
Eight electrons
How many electrons can fit in the third shell about the nucleus?
18 electrons
How many electrons can fit in the fourth shell about the nucleus?
18 electrons
What can be said about an atom that had the same number of protons and electrons?
It is balanced
When is an atom said to be stable?
When it will not readily react with another element
How is the stability of an element determined?
The number of electrons in the outermost shell.
If an atom has a positive charge, what is it known as?
Positive ion
If an atom has a negative charge what is it known as?
A negative ion
What is electricity?
The flow, or transfer of electrons.
What are the two types of electricity?
Current electricity, static electricity
What is conventional flow?
The orientation of electrons flowing from the positive to the negative
What is electron flow?
The orientation of electrons flowing from the negative to the positive
Which is the proper theory for electricity?
Electron flow
what is a conductor?
An element which will easily give up and receive electrons
What is an insulator?
An element which will not easily give up and receive electrons
What will the shell of an insulator look like?
The outer shell will be almost completely full
What is a semi conductor?
An element which, under certain conditions, will act as a conductor, and will under other conditions act as an insulator
What will the shell of a semi conductor look like?
The shell would be approximately half full
What are the five units of electron transfer?
Coulomb, ampere, ohm, voltage, watt
What is coulomb a measurement of?
Quantity
What is the definition of coulomb?
6.28 x 10^ 18
What is an ohm a measurement of ?
Opposition to flow
What is the strict definition of ohm?
The opposition which allows 1 Amp to be moved by 1 volt
What is voltage a measurement of?
Electrical pressure, potential, potential difference, electromotive force
What is the strict definition of voltage?
The electrical pressure required to move one amp through one ohm
What is watt a measurement of?
Electrical power dissipated
What is the strict definition of a watt?
The electrical power dissipated by 1
Amp being moved through 1 ohm by 1 volt
When using a voltmeter, what are you measuring?
Electrical pressure
When using a voltmeter, how is it installed in the circuit?
In parallel
Must polarity be observed with a voltmeter?
Yes
When the range for a voltmeter is unknown, what must be done?
Start at the highest range and work downward
How is a voltmeter used?
With the circuit complete and on
What is an ammeter used to measure?
Rate of electron flow
How is an ammeter used?
With the circuit complete and on
How is an ammeter installed?
In series with the load or circuit
Must polarity be observed with an ammeter?
Yes
What Must be done if the range is unknown?
Start with highest range and work down
What is an ohmmeter used to measure?
Resistance and continuity
How is an ohmmeter used?
The component must be isolated from the circuit, and the ohmmeter is used in parallel with said component
Is polarity an issue with an ohmmeter?
Not unless diodes are considered
What is done if the range is unknown?
Start with the lowest and work up
Two classifications of electricity?
Current, static.
What is current electricity?
The continuous transfer of electrons along a directed path
What is static electricity?
A momentary transfer of electrons due to a momentary imbalance in ions
Do similarly charged particles attract or repel each other?
Repel
Do oppositely charged particles attract or repel each other?
Attract
What is the strength of static attraction or repulsion based on?
Distance between the charges
How will the strength of the charge change?
According to the inverse of the square
= 1
__
X^2
Affects of static charge in aviation?
Interference with electronic navigational equipment, transmission and receiving of communication signals, fire hazard during fueling process, burning out of sensitive avionics
What is the purpose of bonding straps?
To join all the insulated parts of the aircraft so that the aircraft will be the same static charge throughout, and so that there will be continuity path for all electrical circuits
What are static wicks used for?
To help disperse the build up of static
Charges to the atmosphere
Wheat is a natural magnet?
A material that has the property of attaching itself to ferrous materials and which produces a magnetic field external to itself
What is flux ?
Lines of magnetic force flowing external to the magnet
How does flux flow?
They leave the North Pole and enter the south at 90°
Are lines of flux polarized?
Yes
What is one line of flux called?
A maxwell
State the domain theory.
All matter consists of infinitely small magnetic fields called domains, which are randomly arranged, if the material is magnetized, all of the domains align themselves north to south
What is a gauss?
Measurement of flux density
What is a Gilbert?
A measurement of magnetic force
What is retentivity?
The ability of a material to retain the alignment of its domains after the outside magnetizing force is removed
What is permeability?
The ease with which the lines of flux will travel through a material
What is reluctance?
The ability of a material to resist lines of flux
What is true about any naturally magnetized material?
It will eventually lose magnetism
