WHAT ARE ALPHA, BETA and GAMMA RAYS?
Pupils use secondary sources of information to make up a table of properties of alpha, beta and gamma radiations. EQUIPMENT: Radium source + GM tube + scaler + absorber kit. RESOURCES: Duncan5 pg 157 Letts S320-321/ Letts P158-159 CS1 p181 SAFETY: see lesson 9 ________________________________________________________________________ Lesson 12: RADIOACTIVE DECAY WHAT MAKES AN ATOM DECAY? Recall random nature of radiation from previous lessons suggesting some element of chance at work. Hence link to chance of a dice decaying. DEMO 100 dice decaying – collect results and plot bar graph – see typical decay curve and get pupils to explain why this makes sense (same chance but fewer dice means fewer decay). Hence if radioactive atoms also ruled by chance then should see same behaviour if we watch them decay – leads to decay of protactinium EXPT. using GM-tube sensor and SUPERCH software. HALF-LIFE Distribute copies of decay curve and show that time taken to halve no. decaying is always the sa