Deffinitions

Question 1

Longitudinal wave

Answer 1

The particles vibrate along the same direction of the wave

Question 2

Transverse wave

Answer 2

The particles move at right angles to the direction of travel of the wave

Question 3

Frequency i

Answer 3

The number of waves per second

Question 4

Period

Answer 4

The time taken for one wave to pass a point

Question 5

Diffraction

Answer 5

The bending of waves through gaps or around obstacles

Question 6

Refraction

Answer 6

The change in speed of light as it passes from one medium to another

Question 7

Alpha particle

Answer 7

A particle made up of 2 protons and 2 neutrons

It is the nucleus of a helium atom

Question 8

Beta particle

Answer 8

A fast moving electron

Question 9

Gamma ray

Answer 9

Am electromagnet wave of very high frequency and energy

Question 10

Ionisation

Answer 10

The addition or removal of an electron from a neutral atom

Question 11

Activity

Answer 11

The number of nuclear decays per second

Question 12

Absorbed dose

Answer 12

The energy absorbed by a material per unit mass

Question 13

Equivalent dose

Answer 13

The absorbed dose multiplied by the radiation weighing factor

Question 14

Equivalent dose rate

Answer 14

The equivalent dose per unit time

Question 15

Half-life

Answer 15

The time taken for the activity of a radioactive source to decrease to half of it’s original value

Question 16

Nuclear fission

Answer 16

The process in which an unstable, heavy atomic nucleus splits into two or more lighter nuclei with energy being released

Question 17

Chain reaction

Answer 17

When neutrons released in nuclear fission reactions go on to hit other nuclei, causing further fission reactions, and the cycle repeats

Question 18

Nuclear fusion

Answer 18

The process of small nuclei joining together to form a larger nucleus, with energy being released

Question 19

Plasma containment

Answer 19

The use of powerful magnetic fields to prevent hydrogen plasma from physically touching any parts of a nuclear reactor

Question 20

Heat

Answer 20

A measure of the total kinetic energy of the particles in an object

Question 21

Temperature

Answer 21

A measure of the average kinetic energy of the particles in an object

Question 22

Specific heat capacity

Answer 22

The amount of heat energy required to raise the temperature of 1kg of a substance by degrease Celsius

Question 23

Specific latent heat

Answer 23

The amount of heat energy required to change the state of 1kg of a substance

Question 24

Specific latent heat of fusion

Answer 24

The energy required to change 1kg if a solid into a liquid at it’s melting point

Question 25

Specific latent heat of vaporisation

Answer 25

The energy required to change 1kg of a liquid into a gas at its boiling point

Question 26

Pressure

Answer 26

The force per unit area

Question 27

Absolute zero

Answer 27

The temperature it which the pressure in a substance is zero This occurs at -273C or 0k Where we assume the kinetic energy of the particles is zero

Question 28

Boyle’s law

Answer 28

For a fixed mass of gas at constant temperature, pressure is inversely proportional to volume

Question 29

Gay-Lussac’s law

Answer 29

For a fixed mass of gas at constant volume, pressure is directed proportional to temperature (in K)

Question 30

Charles’ law

Answer 30

For a fixed mass of gas at constant pressure, volume is directly proportional to temperature ( in k)

Question 31

Scalar

Answer 31

A quantity that consists of a magnitude (size) only

Question 32

Vector

Answer 32

A quantity that consists of a magnitude and direction

Question 33

Speed

Answer 33

The distance traveled per unit time

Question 34

Average speed

Answer 34

The total distance traveled by an object measured over the total time taken

Question 35

Instantaneous speed

Answer 35

The speed of an object at a particular moment in time

Question 36

Instantaneous speed

Answer 36

The speed of an object at a particular moment in time

Question 37

Velocity

Answer 37

The displacement per unit time

Question 38

Acceleration

Answer 38

The change in velocity per unit time taken

Question 39

Acceleration

Answer 39

The change in velocity per unit time

Question 40

Gravitational field strength

Answer 40

The gravitational force per unit mass

Question 41

Newton’s first law

Answer 41

An object will remain at rest or move at a constant speed in a straight line unless acted upon by an unbalanced force

Question 42

Newton’s second law

Answer 42

F=ma

Question 43

Free fall

Answer 43

The movement of any object under the influence of gravity alone

Question 44

Terminal velocity

Answer 44

For an object in free fall, a constant speed is reached when the upward force on the object is balanced by the downward force on the object

Question 45

Newton’s third law

Answer 45

Every action has an equal but opposite reaction

Question 46

Projectile motion

Answer 46

The curved path taken by a projectile due to its constant horizontal velocity and constant vertical acceleration

Question 47

Satellite

Answer 47

A special type of projectile that follows a circular orbit due to its constant horizontal velocity and constant vertical acceleration

Question 48

Work done

Answer 48

A form of energy which describes the force applied to move an object a certain distance

Question 49

Electrical current

Answer 49

The electrical charge transferred per second

Question 50

Direct Current (D.C.)

Answer 50

The flow of current in one direction only

Question 51

Alternating current (A.C.)

Answer 51

The back and forth flow of current Current changes every fraction of a second

Question 52

Potential difference (voltage)

Answer 52

The energy supplied to each coulomb of charge that passes through a power supply

Question 53

Resistance

Answer 53

The opposition to current flow

Question 54

Ohm’s law

Answer 54

For a fixed temperature, the voltage is directly proportional to the current passing through it

Question 55

Transistor

Answer 55

A semiconductor device that can be used as an electronic switch

Question 56

Electrical power

Answer 56

The electrical energy transferred per second

Question 57

Fuse

Answer 57

A safety device containing a thin wire which will break (melt) when too large a current flows through it