Mod 3 - Final Flashcards
Which one of these statements about electrostatic lines of force is FALSE ?
The tighter the lines of force are together, the stronger the field force is.
The lines always leave positive charges and enter negative ones.
Electrical field force lines can cross over one another.
Electrical field force lines can cross over one another.
The create greater charge levels on substances within the Triboelectric Series, the should be?
As close to one another on the Triboelectric table.
It doesn’t matter where they are on the Triboelectric table.
As far away from each other on the Triboelectric table.
As far away from each other on the Triboelectric table.
When 2 items on the the Triboelectric Series are rubbed together, the one HIGHEST UP gains?
No Charge
A negative Charge
A positive Charge
A positive Charge
The ordered list of insulators in relation to their effect on generating static electricity is called the:
The Fourier Transform List
The Triboelectric Series
The conductivity Index
The Triboelectric Series
Electrostatic lines of force are drawn in which of the following manners?
Leaving negative charge, entering positive charge
Entering negative charge, entering positive charge
Entering negative charge, leaving positive charge
Leaving negative charge, entering positive charge
A coulomb is
one second per ampere
one ampere x second
one ampere per second
one ampere x second
Remember: Q = I * T
The LETTER symbol used in circuit diagrams to denote ELECTROMOTIVE FORCE is the letter ?
I
G
V
R
E or U
E or U
Which one of the following generators of electricity can only ever produce a DC Current?
a magnetism and motion generator
a thermocouple
a piezoelectric crystal
a thermocouple
You can produce a voltage in quarts crystal system by ?
By placing a compressive load on it.
Heating the quartz crystal up to 500°C
Placing it in a very strong magnetic field.
By placing a compressive load on it.
Which one of the following generators of electricity can only ever produce a DC Current?
a photoelectric cell
a piezoelectric crystal
a magnetism and motion generator
a photoelectric cell
A pilot’s crystal microphone in a boom headset uses which form of energy to create electricity?
Chemical
Magnetism and conductor motion
Frictional
Optical
Pressure
Thermal
Pressure
You can generated a voltage directly by using the following :
Magnetism, Water, wind, Chemical, Light and Heat.
Friction, heat, light Chemical, Pressure and Magnetism,
Heat, centrifugal force, friction, kinetic force and Wind.
Friction, heat, light Chemical, Pressure and Magnetism,
If a battery has got an appreciable internal resistance, then …..
no load voltage will be greater than on load voltage
on load voltage will be greater than no load voltage
no load voltage will be the same as on load voltage
no load voltage will be greater than on load voltage
Which of the following actions will recharge a secondary cell ?
Connecting the negative terminal of a voltage source to the anode of the cell and the positive terminal of the voltage source to the cathode of the cell
Connecting the negative terminal of a voltage source to the cathode of the cell and the positive terminal of the voltage source to the anode of the cell
Adding more water to the electrolyte
Connecting the negative terminal of a voltage source to the anode of the cell and the positive terminal of the voltage source to the cathode of the cell
In a voltaic cell, what is the (salt) build-up on the cathode called?
Sulphation
Hydration
Polarization
Sulphation
How many NiCad cells are needed to make a 24VDC aircraft battery?
20
1
12
20
NiCad SG = 1.2
A Lead-Acid battery can be charged by?
Constant Current methods only.
Constant Voltage or current methods.
Constant Voltage methods only.
Constant Voltage or current methods.
The way to determine the charge level of a NICad battery is to?
measure the electrolyte’s specific gravity
completely discharge the battery and measure the charge that it gave out.
measure it’s OFF LOAD terminal voltage.
completely discharge the battery and measure the charge that it gave out.
This Leclanche (Zinc/Carbon) battery would be defined as a?
wet cell
secondary cell
primary cell
primary cell
Which of the following is NOT a Secondary Cell?
LeClanche
Lead Acid
Nickle Cadnium
LeClanche
nickel-cadmium (NiCd), lead acid, and lithium ion batteries.
If a charge current is still entering a battery, after it has become fully charged, it will cause which effect?
Electrolysis (the creation of Hydrogen and Oxygen gasses)
No effect
Decrease the Specific Gravity.
Electrolysis (the creation of Hydrogen and Oxygen gasses)
The specific gravity of an unused aircraft battery can change slightly from day to day, due to daily?
air pressure changes
humidity changes
electrolyte temperature changes.
electrolyte temperature changes.
How many Lead-Acid cells are needed to make a 24VDC aircraft battery?
20
12
1
12
Lead-Acid SG = 2
The state of charge of which battery can be determined by measuring it’s specific gravity?
Both Lead-Acids and NiCads
Lead-Acids only
NiCads only
Lead-Acids only
The specific gravity of a battery’s electrolyte can be measures using a ?
Megger
Hydrometer
Hygrometer
Densiometer
Hydrometer
Note: A hygrometer is an instrument used in monitoring or measuring the level of humidity in the air.
HyGROmeter - air is abit groggy - humidity in air
Constant current charging is the “preferred method” of restoring power to which type of battery?
Le Clanche Cells
Lead-Acid
NiCad
NiCad
To maximize power transfer from a power source the :
Load Resistance should be LESS THAN the Source Resistance
Load Resistance should be EQUAL TO the Source Resistance
Load Resistance should be GREATER THAN the Source Resistance
Load Resistance should be EQUAL TO the Source Resistance
In a circuit containing three resistors of equal value connected in parallel.
If one resistor goes open circuit.
The current in the other two resistors will ?
remain the same
decrease
increase
remain the same
Aiding each other
Opposing Each other
Neither aiding or opposing
Opposing Each other
In a circuit containing three resistors of equal value connected in parallel.
If one resistor goes short circuit.
The current in the other two resistors will ?
remain the same
decrease to zero
increase
decrease to zero
1 Hp = ? Watts
1 Hp = 746 Watts
Copper is a
diamagnetic material
ferromagnetic material
paramagnetic materials
diamagnetic material
A paramagnetic material has a relative permeability :
equal to unity
greater than unity
less than unity
greater than unity
A diamagnetic material has a relative permeability :
equal to unity
greater than unity
less than unity
less than unity
The unit of magnetomotive force (mmf) is ;
The Weber
The tesla
Ampere-turn.
Ampere-turn.
An example of a paramagnetic material is
iron
copper
glass
iron
Copper is Diamagnetic
Which of the following is absolute permeability
µ(mu).
µ(mu)r.
µo(mu).
µ(mu).
Why is Ferrite used in memory circuits
High reluctance
Low permeability
High remanence
High remanence
Magnetic field on a solenoid is
Strongest outside the coil
The same both inside and outside the coil
Weakest outside the coil
Weakest outside the coil
Q
In a fully discharged Lead Acid battery the amount of acid in the water is at its?
(a) Highest
(b) Lowest
(c) It never changes
(b) Lowest
