Measuring the Radioactivity of a Smoke Detector
BlackBoard Notes

======================= Photo - Click for a Larger Version =============================

======================= First Board Section =============================

• Place radiation monitor directly on source and centered
• Always respect radiation sources - no eating or drinking during lab!
• Wash your hands when finished!
  • (Attach 'No Eating…' sign to blackboard in this section)

======================= Second Board Section =============================

• Which isotope of Americium (Am) is in the smoke detector?
  • Look on the Chart of the Nuclides
  • Find isotope and its decay product that are both stable (long half-life, t_½)
    • Label equation below with Mass number ( protons + neutrons) and Atomic Number (# of protons)

  • 

    {isotope – Alpha emitter = Decay product}
           { Is this stable?}

======================= Third Board Section =============================

• Test activity with assorted materials between source & radiation monitor:
  • Paper (1, 2 & 3 sheets)
    • Leave paper for next group!
  • Air gap (~1 cm)
  • Choose 2 of the following (on front bench)
  • Copper
  • Zinc (ZN - dull gray)
  • Steel (Rusty)
  • Tin (SN - shiny)
  • Lead (thick - only 1 piece)
    • Descriptions not needed if pieces labeled with sticky notes

• Calculate mass of Am in smoke detector
  • Follow instructions
    • (omit calculations; they should be able to figure them out from the instructions!!):

======================= Fourth Board Section =============================

• Lab Practical - in 2 weeks!
  • Practice materials on side table
  • Check document on Canvas for skills tested
  • Need something? Ask!

Return to Setup

©	St. Lawrence University	Department of Physics

Revised: 30 May 2023

Canton, NY 13617