Radiation

Question 1

What are the 3 ionising radiations?

Answer 1

• Alpha
• Beta
• Gamma

Question 2

Which radiation is the least penetrating?

Answer 2

Alpha

Question 3

Which radiation is the most ionising?

Answer 3

Alpha

Question 4

What are atoms composed of?

Answer 4

• Electrons (negative)
• Nucleus (positive)
• Protons (positive)
• Neutron (neutral)

Question 5

What is the charge of an electron?

Answer 5

Negative

Question 6

What is the charge of a proton?

Answer 6

Positive

Question 7

What is the charge of a nucleus?

Answer 7

Positive

Question 8

What is the charge of a neutron?

Answer 8

Positive

Question 9

How are Ions made?

Answer 9

Ions are made when an electron is removed or added from an atom.

Question 10

How do you create a positive Ion?

Answer 10

Positive Ions are made by removing an electron or more than one electron.

Question 11

How do you create a negative Ion?

Answer 11

Negative Ions are made by adding an electron or more than one electron.

Question 12

What is Alpha absorbed by?

Answer 12

A few cm of paper.

Question 13

Which radiation is absorbed by a few cm of paper?

Answer 13

Alpha

Question 14

What is Alpha?

Answer 14

Alpha is a Helium nucleus (2 protons 2 neutrons)

Question 15

Which radiation is the slowest?

Answer 15

Alpha

Question 16

Which radiation is the most ionising?

Answer 16

Alpha

Question 17

Which radiation is the most biologically damaging?

Answer 17

Alpha

Question 18

Which radiation is the middle penetrating?

Answer 18

Beta

Question 19

Which radiation is the middle ionising?

Answer 19

Beta

Question 20

Which radiation is absorbed by a few mm of Aluminium or dense material?

Answer 20

Beta

Question 21

What is Beta absorbed by?

Answer 21

• A few mm of Aluminium

* Dense material

Question 22

What is Beta?

Answer 22

Beta is a negatively charged electron ejected from a nucleus.

Question 23

Which radiation has no mass and no charge?

Answer 23

Gamma

Question 24

Which radiation is the most penetrating?

Answer 24

Gamma

Question 25

What speed does Gamma travel at?

Answer 25

The speed of light (3.0x10^8ms^-1)

Question 26

Why does Gamma have no mass?

Answer 26

Gamma is an EM wave.

Question 27

Which radiation is an EM wave?

Answer 27

Gamma

Question 28

Which radiation is absorbed by a few cm of lead or many metres of concrete?

Answer 28

Gamma

Question 29

What is Gamma absorbed by?

Answer 29

* A few cm of lead | * Many metres of concrete

Question 30

What is "activity"?

Answer 30

The activity is a measure of the nuclei that decay in 1 second.

Question 31

What is the equation for activity?

Answer 31

A= N / t

Question 32

What is the unit of activity?

Answer 32

Becquerels (Bq)

Question 33

What does an unstable source emit?

Answer 33

Alpha, Beta, or Gamma

Question 34

What is "half life"?

Answer 34

Half Life is the time it takes for the activity of a source to half.

Question 35

A radioactive source has an activity of 100MBq. If it's half life is 3 hours, calculate it's activity 12 hours later.

Answer 35

6.25MBq

Question 36

The activity of a radioactive source falls from 240MBq to 15MBq in a time of 24 hours. Calculate the half life of the source.

Answer 36

6 hours

Question 37

After 8 hours the activity of a source has decreased to 20MBq. Calculate the initial activity of the source if it has a half life of 2 hours.

Answer 37

320MBq

Question 38

What is "Dosimetry"?

Answer 38

This is the science of measuring the dosage of radioactivity.

Question 39

What is "Absorbed Dose"?

Answer 39

This measures the radiation energy that is absorbed per kilogram of metal.

Question 40

What is the formula for Absorbed Dose?

Answer 40

D = E / M

Question 41

What is the formula " A = N / t " for?

Answer 41

Activity

Question 42

What is the formula " D = E / M " for?

Answer 42

Absorbed Dose

Question 43

What are the units for Absorbed Dose?

Answer 43

* Joules per Kilogram (Jkg^-1) | * Gray (Gy)

Question 44

What is Absorbed Dose usually measured in?

Answer 44

* 1 uGy = (1x10^-6) Gy | * 1 mGy = (1x10^-3) Gy

Question 45

What is 1 uGy equal to?

Answer 45

(1x10^-6) Gy

Question 46

What is (1x10^-6) Gy equal to?

Answer 46

1 uGy

Question 47

What is 1 mGy equal to?

Answer 47

(1x10^-3) Gy

Question 48

What is (1x10^-3) Gy equal to?

Answer 48

1 mGy

Question 49

50 uGy of radiation is absorbed by 500g of body tissue. Calculate the energy absorbed by the tissue.

Answer 49

50 uGy

Question 50

What is "Equivalent Dose"?

Answer 50

Equivalent Dose is a better measure of the biological effect of radiation exposure.

Question 51

What is the formula for Equivalent Dose?

Answer 51

H = D x WR

Question 52

What is the formula " H = D x WR " used for?

Answer 52

Equivalent Dose

Question 53

What is Equivalent Dose measured in?

Answer 53

Sievert (Sv)

Question 54

What factors effect biological damage?

Answer 54

* Total absorbed dose * Equivalent Dose * Time Exposed * Type of radiation * Shielding * Distance * Absorbing tissue type

Question 55

What is "nuclear fission"?

Answer 55

Nuclear fission is the splitting of a large nucleus. A neutron is fired at a Uranium atom, and the neutrons produced go on and on to create a chain reaction. This chain reaction releases a lot of energy.

Question 56

What is "nuclear fusion"?

Answer 56

Nuclear fusion is the joining of 2 smaller nuclei. Nuclear fusion often occurs in stars.

Question 57

What are the advantages of nuclear energy?

Answer 57

* Smaller mass of fuel required compared ti fossil fuels for same energy output * No greenhouse gases * Nuclear fuel will be a longer lasting supply compared to fossil fuels

Question 58

What are the disadvantages of nuclear energy?

Answer 58

* Radioactive waste is produced * Expensive to build and decommission nuclear power stations * Potential for big accidents