Effect of magnetic field Objective To study the effect of applying a magnetic field to the three types of nuclear radiation. Materials Geiger counter 2 slab-shaped magnets on iron yoke Americium (alpha source) Strontium (beta source) Cobalt (gamma source) Go to the online laboratory Procedure 1. Turn on the Geiger counter with the scale set to x1 and allow it to warm up for a few minutes. 2. Take background activity measurements. 3. Place the alpha source into the wooden block. 4. Place the Geiger counter 8 centimeters from the source. In front on the window of the Geiger counter, place a shield of lead sheet with a quarter inch opening in front of its window. 5. With no magnet in place, record the count rate. 6. Add the two slab-shaped magnets in the iron yoke. Set the iron yoke so that it is in line with the path of the beta particles. 7. Record the counts per minute. 8. Replace the alpha source with beta, and gamma source. Repeat step 3-7. Do you know? 1. Does the amount of bending of beta particles increase or decrease when two magnets are used in the experiment? Explain. 2. What results would you expect if a) alpha particles were used? b) gamma rays were used? *back* (C) 1999 Thinkquest Team 27954