Physics for Queensland Units 1 & 2 Sample Lesson plan 5.2
Lesson plans:
Module 5 Radioactive decay and half-life
Pages 2–39 Recommended
• 5.1 The discovery of nuclear radioactivity
• Science understanding
• Explain natural radioactive decay in terms of
• Science as a human endeavour
• Appreciate the significant contributions of scientists such as Marie Curie, Irene Curie-Joliot, Lise Meitner and Otto Hahn who furthered our understanding of radiation and nuclear stability.
• 5.2 Properties of nuclear radiation
• 5.3 Balancing nuclear equations
• Science understanding
• Explain natural radioactive decay in terms of stability.
• Describe alpha, beta positive, beta negative and gamma radiation, including properties of penetrating ability, charge, mass and ionization ability.
• Science as a human endeavour
• Explore advances in medical treatment and imaging that have come from a deepening understanding of the properties of nuclear radiation.
• Science understanding
• Solve problems using balanced nuclear equations.
30 minutes
• 5.4 Types of radioactive decay
• 5.5 Half-life
• Science understanding
• Explain how an excess of mass, protons or neutrons in a nucleus can result in alpha, beta positive and beta negative decay.
• Describe spontaneous alpha, beta positive and beta negative decay using decay equations.
• Explain how a radionuclide will, through a series of spontaneous decays, become a stable nuclide.
• Sub-strand
• Describe the concept of half-life.
90
60 minutes
• 5.2A Shielding effects from a radioactive source
• Solve radioactive decay problems using
and other arithmetic or graphical methods.
• Science inquiry
• Investigate shielding effects and/or the relationship between intensity and distance from a radioactive source.
• 5.2B Intensity and distance from a radioactive source
• Science inquiry
• Investigate shielding effects and/or the relationship between intensity and distance from a radioactive source.
60 minutes
SAMPLE
Physics 2025 v1.0 General senior syllabus links
Topic 2: Ionising radiation and nuclear reactions
Science understanding
Nuclear model and stability
• Explain natural radioactive decay in terms of stability.
60 minutes
• Describe alpha, beta positive, beta negative and gamma radiation, including properties of penetrating ability, charge, mass and ionization ability.
• Explain how an excess of mass, protons or neutrons in a nucleus can result in alpha, beta positive and beta negative decay.
• Solve problems using balanced nuclear equations.
• Describe spontaneous alpha, beta positive and beta negative decay using decay equations.
• Explain how a radionuclide will, through a series of spontaneous decays, become a stable nuclide.
• Describe the concept of half-life.
• Solve radioactive decay problems using
and other arithmetic or graphical methods.
Science as a human endeavour
• Appreciate the significant contributions of scientists such as Marie Curie, Irene Curie-Joliot, Lise Meitner and Otto Hahn who furthered our understanding of radiation and nuclear stability.
Science inquiry
• Investigate shielding effects and/or the relationship between intensity and distance from a radioactive source.
Unit objectives
1. Describe ideas and findings about ionising radiation and nuclear reactions.
2. Apply understanding of ionising radiation and nuclear reactions.
3. Analyse data about ionising radiation and nuclear reactions.
4. Interpret evidence about ionising radiation and nuclear reactions.
5. Evaluate processes, claims and conclusions about ionising radiation and nuclear reactions.
6. Investigate phenomena associated with ionising radiation and nuclear reactions.
Supporting resources (available via Oxford Digital)
• Module 5 Prior knowledge quiz
• Worked solutions
• Lab technician notes and risk assessments
• Videos
Things to know before teaching Module 5 Radioactive decay and half-life
Prior knowledge
This module builds on knowledge and skills gained from Module 4 Nuclear model and stability. To assess prior knowledge, ask students to complete the Module 5 Prior knowledge quiz before they start the module. This will help them identify gaps in their understanding and address them before engaging with more complex content.
It might be helpful to review the following:
1. The nuclear model of the atom
2. X A Z Nuclide nomenclature
3. Alpha, beta and gamma radiation
4. Analysing and interpreting graphs showing inverse-square relationships
5. Index laws
General teaching tips
There is a lot of content to cover in this module. It is recommended to use class time for completing practicals, activities and working on formulas. Assign sections for reading as homework. See also the general teaching tips from Chapter 1 if you haven’t done so already.
SAMPLE
Ensure students know how to access the fully worked solutions to Check your learning questions, and why these are only available at the teacher’s discretion.
By now students should have realised that the modules in the student book are ‘chunked’ into small, understandable increments (Lessons 5.1, 5.2 and so on). These help the teacher see natural breaks in the content. This enables students to reflect on the ideas presented by way of the Check your learning questions. This halt to new content at strategic points permits students to have time to think about what they have just experienced.
Lesson 5.2: Properties of nuclear radiation
Pages 6–13
Total time: 60 minutes
Learning intentions and success criteria
By the end of this lesson, students will be able to do the following:
LEARNING INTENTION
Know what alpha, beta positive, beta negative and gamma radiation are.
Understand the properties of alpha, beta positive, beta negative and gamma radiation, including penetrating ability, charge, mass and ionisation ability.
SAMPLE
SUCCESS CRITERIA
• I can define alpha, beta positive, beta negative and gamma radiation.
• I can define penetrating ability and ionisation ability.
• I can describe the penetrating ability, charge, mass and ionisation ability of alpha, beta positive, beta negative and gamma radiation.
Understand shielding effects.
Understand the relationship between intensity of radiation and distance from the radioactive source.
Physics 2025 v1.0 General senior syllabus links
• Unit 1: Thermal, nuclear and electrical physics
• I can explain the relationship between intensity of radiation and shielding.
• I can explain the relationship between intensity of radiation and distance from the radioactive source.
• Topic 2: Ionising radiation and nuclear reactions (Nuclear model and stability)
• Science understanding
o Explain natural radioactive decay in terms of stability.
o Describe alpha, beta positive, beta negative and gamma radiation, including properties of penetrating ability, charge, mass and ionization ability.
• Science inquiry
o Investigate shielding effects and/or the relationship between intensity and distance from a radioactive source.
Teacher considerations
• It is good to introduce the use of a Geiger counter early on. Access a video demonstrating the use of a Geiger counter on Oxford Digital.
• Students could use a graphic organiser (e.g. the Frayer model) to show the characteristics of each type of radiation. These characteristics should include its definition, symbol, penetrating ability, charge, mass and ionisation ability.
Classroom activities
ACTIVITY
SAMPLE
Starter activity: Lesson overview 5
Teacher considerations
• You may like to display a printed version of the learning intentions and success criteria on the board or write them on the board for students to refer to as they complete the lesson.
Instructions for students
• Read through the learning intentions and success criteria for the lesson.
• Make sure that you understand what each cognitive verb means.
Oxford Digital
• Learning intentions and success criteria
5.2A Classroom activity: What do you remember about nuclear stability?
10 minutes Teacher considerations
• Refer students back to Module 4 Nuclear model and stability if they need support answering the questions.
Instructions for students
• Revise your understanding of nuclear stability by answering the following questions:
o Describe the nuclear model of the atom.
o Explain the stability of a nuclide in terms of the operation of strong nuclear force over very short distances, electrostatic repulsion, and the relative number of protons and neutrons in the nucleus.
• Alternatively, complete the Module 5 Prior knowledge quiz.
Feeling unsure?
• Go back to Module 4 Nuclear model and stability to revise your understanding.
5.2B Classroom activity: How do the forms of nuclear radiation compare?
20 minutes Teacher considerations
SAMPLE
• Students may benefit from a short class discussion reviewing the properties of the four forms of radiation. You could use this to provide scaffolding for students before they go off and create diagrams to demonstrate their understanding.
Instructions for students
• As a class, discuss the following:
o What is the definition of ionising (nuclear) radiation?
o What is the penetrating power of nuclear radiation?
• Create four separate diagrams that compare the properties of the four forms of radiation: penetrating ability, charge, mass and ionisation ability.
Feeling unsure?
• Watch the ClickView video on Types of nuclear radiation.
Oxford Digital
• Module 5 Prior knowledge quiz
Website
• ClickView video: Types of nuclear radiation
5.2C Classroom activity: How does distance affect radioactivity?
20 minutes Teacher considerations
• This activity requires an access code and you will need to register to use FARLabs. Walk through the instructions with students and make sure they know what they are doing.
• If you cannot access FARLabs, try the alternative activity.
• You may need to provide students with support to complete calculations during the validation stage. You could demonstrate an example and ask students to pick other data points for their own answers.
Instructions for students
Website
• FARLabs: Exploring the Intensity of Radiation
• FARLabs: Radioactivity in society
Oxford Digital
• Access the Exploring the Intensity of Radiation virtual lab through Oxford Digital. There are up to eight stations that you can use, so you may need to form groups and complete this activity together.
• Use the simulator to generate data on number of counts recorded by a Geiger counter as distance increases.
o Individually or in your group, decide on which trials you wish to do (IV: gap size).
SAMPLE
o Validate whether your data follows the inverse-square law by substituting values into the formula that relates intensity and distance.
• Alternatively, download the data set in the “What you’ll need” column and plot the data. Validate whether your data follows the inverse-square law by substituting values into the formula that relates intensity and distance.
Feeling unsure?
• The validation of your data against the inverse-square law can be tricky! If you’re feeling unsure, check with your teacher to get some support with calculations.
Dig deeper
• Explore the FARLabs website. You can read more about uses for radioactivity and engage with other available simulations to further your understanding.
• Intensity vs distance data set
Review and consolidate 5 minutes Teacher considerations
• Run through the key ideas with students. You can do this as a class discussion, or provide students with a question that they must answer as an exit ticket. The following dot points may help:
o Any radiation that can remove an electron from an atom and create a heavy positive ion and a free electron is ionising radiation.
o Ionising radiation includes electromagnetic radiation (gamma rays, X-rays and ultraviolet radiation) and energetic particles such as alpha and beta particles.
o The forms of ionising radiation can be distinguished by their charge, mass, penetrating ability, ionisation ability, and deflection in magnetic and electric fields.
SAMPLE
o The measured intensity of a nuclide decreases in an inverse-squared relationship with distance.
o The measured intensity of a nuclide decreases exponentially with thickness of the shielding material.
• It is a good idea to assign reading the practicals for homework. It will help save class time, since students should come into the lesson with some idea of what they will be doing, and the risks involved in the experimental work.
Instructions for students
• Before the end of class, you will discuss the key ideas that you have learnt in the lesson. Make sure feel confident with:
o describing the properties of the different types of radiation
o describing the effect of distance and shielding on radioactive intensity.
• Your teacher will then assign you with some homework.
Additional activities ACTIVITY
SAMPLE
• Make sure students know where to find the required readings in Oxford Digital.
Instructions
for students
• Complete all of the Check your learning activities in Lesson 5.2.
• Read through Practicals 5.2A and 5.2B and make sure you have a rough idea of what you will be doing. Read through the risk assessment for each practical.
Oxford Digital
• Practical 5.2A Shielding effects from a radioactive source
• Practical 5.2A Risk assessment
• Practical 5.2B Intensity and distance from a radioactive source
