Geoff M3 Questions

Question 1

Name the particles that make up an atom

Answer 1

Protons, Neutrons, electrons

Question 2

What is the charge of a proton

Answer 2

Positive

Question 3

What is the charge of a neutron

Answer 3

Neutral

Question 4

What is the charge of a electron

Answer 4

Negative

Question 5

What is the value of a charge in a proton

Answer 5

0.1602x10^-18

Question 6

What is the value of an electron

Answer 6

-0.1602x10^-18

Question 7

What is a charged atom called

Answer 7

Ion

Question 8

What is a molecule

Answer 8

A neutral group of 2 or more atoms

Question 9

How are atoms bonded together in a molecule

Answer 9

Chemically

Question 10

What charge is held by a cation

Answer 10

Positive

Question 11

What charge is held by an anion

Answer 11

Negative

Question 12

What is a compound

Answer 12

Composes of atoms from more then one element

Question 13

What is the outer shell of an atom called

Answer 13

Valence shell

Question 14

How many atoms would be found in the outer shell for a conductor

Answer 14

Less then 4

Question 15

How many electrons would be found in the outer shell of a insulator

Answer 15

4 or more

Question 16

How many electrons would be found in the outer shell for a semi-conductor

Answer 16

Exactly 4

Question 17

Adding a foreign atom to a molecule is called what

Answer 17

Doping

Question 18

Give 2 examples of insulators

Answer 18

Mica, porcelain

Question 19

How can static electricity be produced

Answer 19

Contact, friction or induction

Question 20

A glass rod rubbed with fur will hold what sort of charge

Answer 20

Negative

Question 21

A glass rod rubbed with silk will hold what charge

Answer 21

Positive

Question 22

Electrons that move from one material to another are called what

Answer 22

Free electrons

Question 23

When brought close together what will like charges do to each other

Answer 23

Repel

Question 24

When brought close together what will unlike charges do

Answer 24

Attract

Question 25

What is the SI unit of charge

Answer 25

Coulomb

Question 26

How do we calculate current density

Answer 26

Current density=current/cross sectional area

Question 27

What is the maximum temp a wire can be heated to

Answer 27

60*c

Question 28

When we state a cables capacity what value is ambient temperature

Answer 28

25*c

Question 29

If DC is applied to water what gas is generated at the positive pole

Answer 29

Oxygen

Question 30

If DC is applied to water what gas is produced at the negative p9le

Answer 30

Hydrogen

Question 31

Decomposition of chemical compounds by passing an electric current through a liquid is called what

Answer 31

Electrolysis

Question 32

In a battery what is the conducting liquid called

Answer 32

Electrolyte

Question 33

What equipment provides a visualisation of rapidly varying process in electrical engineering

Answer 33

Oscilloscope

Question 34

What equipment provide a visualisation of rapidly varying process in electrical engineering and record it

Answer 34

Oscillograph

Question 35

What is the name given to the means of producing a picture using an electron beam

Answer 35

Braun tube CRT

Question 36

What is the unit for potential difference

Answer 36

Voltage

Question 37

What does EMF stand for

Answer 37

Electromotive Force

Question 38

What is EMF

Answer 38

Electrical charges will exert a push or pull force on each other without coming into contact with one another

Question 39

What is the unit for voltage

Answer 39

Volt

Question 40

What are the 2 kinds of electrical voltage

Answer 40

DC and AC

Question 41

Describe DC voltage

Answer 41

A voltage has the same polarity over time even if the values changes

Question 42

Describe AC voltage

Answer 42

If size and polarity of the voltage changes

Question 43

If we want to measure voltage how should we connect the voltmeter

Answer 43

In parallel with the circuit

Question 44

What is electric current

Answer 44

The flow of electrical charges in a curtain direction

Question 45

What is the equation to calculate current

Answer 45

I=Q/t

Question 46

What is the unit for current

Answer 46

Amperes

Question 47

For a current of 1 amp to flow how many electrons need to pass a point in 1 second

Answer 47

6.24x10^18

Question 48

To measure current how should we connect our meter

Answer 48

In series

Question 49

What is the unit for resistance

Answer 49

Ohms

Question 50

Draw ohms law triangle

Answer 50

V IXR

Question 51

What is the unit for conductance

Answer 51

Siemens

Question 52

What do we use to generate electricity from light

Answer 52

Photocells

Question 53

The potential energy stored in an electron is measured in what unit

Answer 53

Electron volts

Question 54

If we use heat to generate electricity what is it called

Answer 54

Thermionic

Question 55

If we use pressure to generate electricity what is it called

Answer 55

Piezo electric effect

Question 56

List a few examples that uses pressure to generate electricity

Answer 56

Crystal microphone, Crystal loudspeaker, lighters, gas lighters, pressure gauges and dynamometers

Question 57

Describe the basic requirements of a battery

Answer 57

2 different metals suspended in an electrolyte

Question 58

What action is it called for what happens in a battery cell

Answer 58

Galvanic action

Question 59

What term is used to describe electric generation by moving a conductor in a magnetic field

Answer 59

Induction

Question 60

What will determine the amount of voltage generated through induction

Answer 60

Magnetic field strength, length of wire Speed of motion

Question 61

What do we call a one use only battery cell

Answer 61

Primary cell

Question 62

What do we call a rechargeable cell

Answer 62

Secondary cell

Question 63

What is the unit of battery cell capacity

Answer 63

Ampere hours

Question 64

What are the most common metals used for thermocouples

Answer 64

Chromel and alumel

Question 65

Where do we use thermocouples

Answer 65

Measuring exhaust gas temps

Question 66

What voltage can a photocell produce

Answer 66

0.6v

Question 67

Describe a sinusodial waveform

Answer 67

Equal alternation positive half reflects negative half

Question 68

What do we call a waveform that is not equal positive and negative

Answer 68

Superimposed

Question 69

What is a period

Answer 69

Time taken to achieve 1 complete cycle

Question 70

How do we calculate peak value from RMS

Answer 70

RMSx1.414

Question 71

How do we calculate RMS from peak value

Answer 71

Peak x 0.707

Question 72

What voltage can be achieved from a 3phase generator

Answer 72

115v phase to neutral and 200v from phase to phase

Question 73

How far apart are the phases in a generator

Answer 73

120 degrees