Add revision topic title in here

1. How to use: • Write name of main revision topic on spine of fish; • Choose 6 Big Ideas for the topic and add these to Big Idea boxes 1-6; • Add 3 key points for each key idea. Add Big Idea 1 Add Big Idea 2 Add Big Idea 3 Add Key Point 1 Add Key Point 1 Add Key Point 1 Add Key Point 2 Add Key Point 2 Add Key Point 2 Add Key Point 3 Add Key Point 3 Add Key Point 3 Add revision topic title in here Add Key Point 3 Add Key Point 3 Add Key Point 3 Add Key Point 2 Add Key Point 2 Add Key Point 2 • Top tips: • Use a different colour for each Big Idea; • Use pictures and symbols where you can • Use bullet points for Key points 1-3 Add Key Point 1 Add Key Point 1 Add Key Point 1 Add Big Idea 4 Add Big Idea 5 Add Big Idea 6

2. How to use: • Write name of main revision topic on spine of fish; • Choose 6 Big Ideas for the topic and add these to Big Idea boxes 1-6; • Add 3 key points for each key idea. Alpha particles a Beta particles b Gamma rays g Helium nucleus made of 2 neutrons and 2 protons Short wavelength radiation emitted from the nucleus High speed electron Small and less ionizing & stopped by thin sheet of aluminium Wave travels long way but weakly ionizing & stopped by cm of lead Large and strongly ionizing & stopped by sheet of paper Positive charge – deflected by magnetic and electric fields Negative charge – deflected in opposite way to a in electric & magnetic fields No charge and not deflected by electric and magnetic fields Radioactivity Radioactive decay is random & unaffected by external conditions Gamma used for medical treatment & equipment sterilisation Half-life is the same for any sample of a particular element Unstable radioactive nuclei become stable by emitting radiation and turn into other elements Beta used for paper thickness testing and medical tracers Time taken for count-rate to fall to half its initial level • Top tips: • Use a different colour for each Big Idea; • Use pictures and symbols where you can • Use bullet points for Key points 1-3 • Handwritten is best Alpha used for smoke alarms Isotopes of elements have different numbers of neutrons in nucleus Time taken for the number of parent atoms in a sample to halve Observing radiation Uses of radioactivity Half-life Dr Thomson’s source : AQA Science Revision Guide