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Radioactivity and Atomic Physics Explained

1: Why Study Radioactivity?

Activity to match types of non-nuclear radiation with detector

Radioactivity is important because it can help us do lots of useful things.  But it can also be harmful.  MORE

2. Alpha, Beta & Gamma

Simulation of a smoke detector

In this lesson we'll introduce the three most important kinds of nuclear radiation: alpha, beta and gamma.  MORE

3. Half-life part 1

Simulation showing how count rate changes with time

Radioactivity tends to decrease over time.  For some jobs we want the radioactivity to decrease quickly.  MORE

4: Background Radiation

Activity demonstrating origins and effects of background radiation

We are bombarded by radiation all the time quite naturally.  This is called background radiation.  MORE

5. How Radiation Harms

Animation of an alpha particle entering some skin cells

Large doses of radiation make us ill quickly.  Smaller doses increase our risk of cancer much later.  MORE

6. Science and Risk

Activity assessing chances and consequences of a risk

This lesson is about How Science Works.  We'll look at an example of how scientists might investigate the effects of a nuclear accident.  MORE

7: Atoms 1: Early History

Activity showing how the idea of atoms has changed with time

Our story begins with the Ancient Greek philosophers, who were at their peak for 200 years from about 500 BC.  MORE

8. Atoms 2: Electrons

What you get instead of a spark in very low pressure gas

During the late 19th and early 20th century scientists developed the idea that atoms were made up of smaller parts.  MORE

9. Atoms 3: The Nucleus

Simulation of Rutherford's discovery of alpha and beta radiation

In this lesson we'll see how radioactivity was discovered and how radiation was classified into alpha, beta and gamma.  MORE

10: Changes to the Nucleus

Explaining the nuclear equation for beta minus decay

Alpha, beta and gamma radiation change the pattern of protons and neutrons in an atomic nucleus.  MORE

11. Ionization & Detection

Simulation of a gamma source knocking electrons off the walls of a cloud chamber

We'll look at ionization in more detail and how it can be used to measure and detect nuclear radiation.  MORE

12. Stability, Fusion & Fission

Animation of fusion of heavy nuclei in a supernova explosion

Nuclear radiation happens because it causes a nucleus to become more stable.  MORE

13: Binding Energy & Mass Defect

Explaining the average binding energy per nucleon curve

We'll look in more detail at the amount of energy released when nuclei becom more stable.  MORE

14. Nuclear Power

Animation of a nuclear power station

This lesson is more about the science of nuclear power plants than the politics, which we deal with in lesson 6.  MORE

15. Half-life part 2

Activity to show constant half-life

We'll see what half-life means and why radioactivity changes with time.  MORE

16: Half-life part 3

A tour of the decay equation

This lesson shows how we can use slighltly more advanced mathematics to deal with fractions of a half-life.  MORE

Power Plant Simulation

A standalone nuclear power plant simulation

This is a very sophisticated power plant simulation.  It's not a formal lesson though there is lots of explanation. MORE



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