Basic Principles

Question 1

What is a current consuming device, consumers or loads?

Answer 1

Components which need electrical power

Question 2

What determines the configuration of the electrical system?

Answer 2

The type and role of the aircraft

Question 3

What type of a system does a light training aircraft with limited electrical equipment have?

Answer 3

14 volt direct current (DC)system similar to a car

Question 4

What system does a larger twin turbine aircraft have?

Answer 4

28 volt direct current system as well as a limited amount of alternating current (AC) provided by an inverter which converts DC to AC.

Question 5

What is the primary electrical system on a large modern jet liner?

Answer 5

AC

Question 6

What is the phase voltage, line voltage and frequency of a modern jet airliner?

Answer 6

Phase voltage = 115v
Line voltage = 200v
Frequency = constant at 400Hz

Question 7

How is an electric current produced?

Answer 7

When electrons are encouraged to flow in a orderly way through a conductor.

Question 8

What is a conductor?

Answer 8

Any material that readily allows electrical current to flow through it.

Question 9

What must a circuit be for current to flow?

Answer 9

Complete or closed

Question 10

What is Direct Current (DC)?

Answer 10

Current flowing in one direction only.

Question 11

What is Alternating Current (AC)?

Answer 11

Direction of travel of the electrons alternates.

Question 12

What does an atom consist of?

Answer 12

Protons - positive charge
Electrons - negative charge
Neutrons - no charge

Question 13

What does the nucleus of an atom consist of and what is it’s charge?

Answer 13

Nucleus of atom consists of protons and neutrons tightly bound together.

The nucleus always positively charged (as protons are positively charged and neutrons have no charge).

Question 14

When is an atom electrically neutral overall?

Answer 14

If each atom has the same number of electrons and protons

Question 15

Where can electrons be found?

Answer 15

They surround the nucleus of an atom.

Question 16

What are free electrons?

Answer 16

Electrons not tightly bound to the nucleus.

Therefore, they can be encouraged to jump from one atom to another through the material.

Question 17

What is an ion?

Answer 17

An atom or molecule where the total number of electrons does not equal the total number of protons.

Question 18

What is an insulator?

Answer 18

When materials cannot easily conduct electrical current due to tightly bound electrons which resist movement between atoms.

Question 19

Give examples of insulators

Answer 19

Rubber
Wood
Plastic

Question 20

What is a conductor?

Answer 20

When materials easily conduct electrical current.

Due to electrons being able to easily move easily from atom to atom through the structure.

Question 21

Give examples of conductors

Answer 21

Copper
Gold
Silver
Aluminium

Question 22

What is the purpose of a battery in a circuit?

Answer 22

Supplies the energy to push electrons through the circuit.

In other words provides driving force for electrical current.

Question 23

What is inside a battery?

Answer 23

Two electrodes separated by an electrolyte.

Question 24

What is an electrolyte?

Answer 24

A special substance that contains many ions, making it very electrically conductive.

Question 25

What is a positive and negative terminal?

Answer 25

Electrolyte produces a chemical reaction that removes electrons from one electrode and adds them to the other. Thus, one electrode becomes negatively charged And the other positively charged.

Question 26

What is electrical potential or voltage or the electromotive force (EMF)?

Answer 26

The difference in charge between negative and positive terminal. The difference in charge is what provides the driving (motive) force to move electrons around a circuit. Thus, generating DC current.

Question 27

What is the potential difference measured in?

Answer 27

Volts

Question 28

What is an open circuit?

Answer 28

Open circuit - no current flows | Flow ceases when the circuit is interrupted, by opening the switch.

Question 29

What is a closed circuit?

Answer 29

Closed circuit - current flows | A continuous circulation of electrons through the conductor and battery as long as circuit is closed.

Question 30

What is an electron flow?

Answer 30

Electrons flow from negative to positive

Question 31

What is conventional flow?

Answer 31

Flow from positive to negative

Question 32

What is electricity?

Answer 32

A form of energy resulting from existing charged particles.

Question 33

What has electrical charge and how is it measured?

Answer 33

Electrons and protons have electrical charge and is measured in Coulombs C.

Question 34

What is an anion?

Answer 34

Atom that gains one or more electrons (negative ion).

Question 35

What is a cation?

Answer 35

Atom that loses one or more electrons (positive ion).