1. To know how different forms of radiation behave. Who am I? 1.Not dangerous from a distance. 2.Travels as a wave. 3.Can pass through paper. 4.Has a helium nucleus. 5.Can Pass through lead. 6.Stopped by aluminium. 7.Tiny electron. Alpha, beta or gamma?

2. To know how different forms of radiation behave. Success criteria- Recognise characteristics of ionising radiation and how they are similar and different. State where background radiation comes from and draw a pie chart to show this. State uses of different forms of radiation. Describe what is meant by half life. Calculate half life of radioactive substances.

3. To know how different forms of radiation behave. http://www.bbc.co.uk/learningzone/clips/alph a-beta-and-gamma-radiation/10679.html http://www.bbc.co.uk/learningzone/clips/alph a-beta-and-gamma-radiation/10679.html Watch video- In pairs summarise what we learnt last lesson.

4. Thin mica Thin aluminium stops BETA Thick lead reduces GAMMA Skin or paper stops ALPHA    To know how different forms of radiation behave.

5. Where does radiation come from?

6. To know how different forms of radiation behave. Source Percentage of total radiation Rocks55% Air25% Cosmic15% Building materials5% http://www.bbc.co.uk/schools/gcsebitesize/sci ence/add_aqa_pre_2011/radiation/backgroun dradiationrev1.shtml

7. To know how different forms of radiation behave.

8. The time radioactivity takes to reach half its dose What is “Half Life”? The time taken for half the radioactive atoms to decay OR Additional Science Chapter 13 To know how different forms of radiation behave.

9. Number of popcorn left 16 12 8 4 0 0 10 20 30 40 50 Time (seonds) Half-life of the popcorn = 10s Example of half-life, using a pan of popping popcorn Chapter 13 To know how different forms of radiation behave.

10. 20s40s 30s 10s 50s 0s Number of popcorn left 32 24 16 8 0 0 20 40 60 80 100 Time (seconds) Half life of the popcorn = 20s The half life of the popcorn is 20s The sample contains 32 popcorn at the start. How many will be left after 60s? ? Answer = 4 Additional Science Chapter 13 To know how different forms of radiation behave.

11. Number of nuclei remaining 480 360 240 120 0 0 433 866 1299 1732 2165 Time (years) 1. How many will be left after 1300 years? 2. How many years will have passed before it is harmless? Nuclei 480 240 120 60 30 16 8 Years 433 433 433 433 433 433 Question on half life Answer1 Answer 2 Explanation Half Life 1 2 3 4 5 6 1. 60 nuclei 2.6 x 433 years = 2598 years The half life of americium is 433 years. The example contains 480 nuclei. Additional Science Chapter 13 To know how different forms of radiation behave.

12. Time (Years)Activity (Bq) 010000 206200 403840 602380 801480 100920 120570 140350 160220 180130 20080 22050 24030 26020 28012 3008 3205 3403 3602 3801 4001 A Geiger-Müller tube is used to record the activity of a sample over a period of time. The results are shown in the table. 1.Plot a graph of your results. 2.Find the half life of the substance. 3.The count rate of your element is unaffected when paper is placed between the source and the Geiger– Müller tube, but drops to almost zero when 5 mm aluminium is used. Use this information to write the decay equation for your element.

13. To know how different forms of radiation behave. Success criteria- Recognise characteristics of ionising radiation and how they are similar and different. State where background radiation comes from and draw a pie chart to show this. State uses of different forms of radiation. Describe what is meant by half life. Calculate half life of radioactive substances.

14. To know how different forms of radiation behave. Radiation Uses or radiation Background radiation Different types of radiation Alpha Beta Gamma Ionising