Nuclear Radiation

Question 1

What are the 3 different types of radiation?

Answer 1

Alpha, Beta, and Gamma

Question 2

What is an alpha particle?

Answer 2

An alpha particle is a nucleus of a helium atom

Question 3

What is a beta particle?

Answer 3

A beta particle is a fast moving electron

Question 4

What is gamma radiation?

Answer 4

Gamma radiation is a type of electromagnetic wave

Question 5

What charge do alpha particles have?

Answer 5

They have a positive charge

Question 6

What charge do beta particles have?

Answer 6

They have a negative charge

Question 7

What charge do gamma rays have?

Answer 7

They don’t have a charge, as they are electromagnetic waves

Question 8

What is larger - an alpha particle or a beta particle?

Answer 8

Alpha particles are larger

Question 9

What speed do gamma rays travel at?

Answer 9

• 300,000,000 m/s

* 3x10^8

Question 10

What can be used to absorb alpha radiation?

Answer 10

20cm of air or a thin sheet of paper

Question 11

What can be used to absorb beta radiation?

Answer 11

3cm of aluminium

Question 12

What can be used to absorb gamma radiation?

Answer 12

Several cm of lead or a few metres of concrete

Question 13

Why are atoms usually neutral?

Answer 13

They have the same number of negative electrons as they do positive protons, which therefore give it no charge overall

Question 14

What causes ions to be created?

Answer 14

When an electron is either attracted to or repelled from an atom, which causes the atom to become charged.

Question 15

If an electron is lost, what charge will the ion have?

Answer 15

Positive charge

Question 16

What is an ion?

Answer 16

A charged particle

Question 17

What radiation causes the most ionisation?

Answer 17

Alpha radiation

Question 18

Why do beta particles cause less ionisation?

Answer 18

They are smaller, so do less damage

Question 19

Give the name and units for each letter in the equation -

A=N/t

Answer 19

A= Activity, Baqurels, Bq
N= Number of decays, no unit 
t= Time, Seconds, S

Question 20

In what 3 ways can controlled ionisation be beneficial?

Answer 20

Can be used to diagnose and treat certain illnesses

To protect people, such as smoke detectors

In industry, such as monitoring newspaper thickness in a paper mill

Question 21

What is shielding?

Answer 21

When materials that absorb radiation are used to protect objects which are sensitive to the types radiation

Question 22

What is absorbed dose?

Answer 22

Absorbed dose is how much energy per kilogram, from radiation, has been received

Question 23

What is absorbed dose measured in?

Answer 23

Grays, Gy

Question 24

Give the name and units of what each letter stands for in the equation-

D=E/m

Answer 24

D= Absorbed Dose, Grays, Gy
E= Energy, Joules, J
m= Mass, Kilograms, Kg

Question 25

Give the name and units of what each letter stands for, in the equation - H= WR x D

Answer 25

``` H= Equivalent Dose, Sievert, Sv D= Absorbed Dose, Grays, Gy WR= Radiation Weighting Factor, no units ```

Question 26

What is background radiation?

Answer 26

Background radiation is radiation from our surroundings, which is normally at a very low level

Question 27

What are some examples of natural sources of radiation?

Answer 27

Radon gas from rocks and soil Gamma rays from the ground Carbon and Potassium in our bodies Cosmic rays from outer space

Question 28

What are some artificial sources of radiation?

Answer 28

Medical applications, such as X rays and radionuclides Fallout from weapons testing Nuclear waste from power stations

Question 29

How is radiation used in medical practices?

Answer 29

For xrays, scans and cancer treatments

Question 30

What can radiation be used for in industry?

Answer 30

To test and inspect welds for flaws

Question 31

What is equivalent dose measured in?

Answer 31

Sieverts, Sv

Question 32

What is the definition of a half life?

Answer 32

The half life is the time taken for the activity of a radioactive source to fall to half of its previous value

Question 33

What happens to a radioactive substance when it emits radiation?

Answer 33

Its nucleus decays

Question 34

What is activity?

Answer 34

The rate of decay of an atoms nucleus

Question 35

What happens in a fission reaction?

Answer 35

A nucleus with a large mass number splits, leaving 2 nuclei with smaller mass numbers, along with some neutrons

Question 36

What are the 2 types of nuclear fission?

Answer 36

Spontaneous, and Induced

Question 37

What type of fission occurs when there is an unstable nucleus?

Answer 37

Spontaneous Fission

Question 38

How is Induced fission started?

Answer 38

Large atoms are forced to split, by bombarding them with with slow moving neutrons.

Question 39

What is an example of a moderator, and what is it used for?

Answer 39

Graphite is a moderator which is used to slow down the fast moving neutrons released by a fission reaction. This increases the chances of further reactions happening.

Question 40

What is a fission reaction managed by?

Answer 40

It's managed by using a control rod, made of boron, to absorb some of the slow neutrons

Question 41

How do uncontrolled fission reactions happen?

Answer 41

* a neutron enters the split nucleus * from this, both energy and products are released * this starts a chain reaction, which very quickly increases the number of nuclei involved

Question 42

What is nuclear fusion?

Answer 42

Nuclear fusion is the joining of 2 or more smaller nuclei, to form a larger one

Question 43

Where do fusion reactions take place?

Answer 43

In the sun and in other stars

Question 44

In a nuclear power station, what is the heat released by the nuclear reaction used for?

Answer 44

To produce steam in the heat exchanger

Question 45

What is the steam produced used for in a nuclear power station

Answer 45

To turn the turbine, which turns the generator to produce electricity

Question 46

What biological effects does radiation have?

Answer 46

It can kill or damage living cells If the DNA of a cell is altered it can grow into a tumour

Question 47

What are some environmental hazards of radiation?

Answer 47

Very high doses can be fatal | Lower doses cause sickness and mutations