Module 3 Flashcards
What is potential difference
A potential difference always arises between two differently charged points. An electrical voltage occurs, as soon as there is a deficiency of electrons at one point and an excess of electrons in another point.
What device is used to separate charges
A generator
What are current transformers
Current transformers (CTs) are special transformers which allow the measurement of AC currents without breaking the current-carrying leads.
What is the charge of a single electron
0.1602x10 to the -18
A charged atom is said to be what
Ionised
What is a molecule
A molecule is an electrically neutral group of two or more atoms held together by chemical bond
What is a cation
A positively charged ion
What is an anion
A negatively charged ion
How are molecules held together
Covalent bonds
How are ionic compounds held together
Ionic bonds
How are intermetallic compounds held together
Metallic bonds
Generally how many electrons do good conductors have in the outer valence orbit
4
What are insulators also known as
Non conductors
During static electricity what are free electrons
Electrons in the outer layer that can be handed to the other material
What is charging by induction
A charged rod is placed near a metal bar it steals the charge
What is Coulomb’s law
Opposites attract and likes repel
What temperature must cables not exceed
60°c
Is pure water a conductor
No
Tap water is due to the amount of impurities
What is electrolysis
The decomposition of chemical compounds by passing an electrical current through a liquid
What is the conducting substance called in the electrolysis process
Electrolyte
What can be done with an oscillograph
Processes in electrical engineering can be recorded
What can be done with an oscilloscope
Processes can be visualised but not recorded
Why is the electron beam oscilloscope used today
Easy to operate, versatile and shock resistant
What is a potential difference
A potential difference arises between two differently charged points