Shirley Cesair (Henderson School) Handout: The Peanut Wizard; Electrical
described an activity in which kindergarten students put 8 peanuts inside a plastic "baggy" for an exercise in math / counting. We examined the peanuts, and developed a description of them.
Shirley then led an exercise in which she blew up a balloon and rubbed it against felt. Then, she put the balloon over small pieces of paper, which became attached (stuck) to the balloon because of the static charge produced on the balloon by rubbing. She repeated the same thing with granulated sugar, which also became attached to the balloon, for the same reason. Interesting!
Sarah Brennan (Robeson HS)
Common to all Gases
Sarah gave 35 cc syringes and balloons to each of us.
Karlene Joseph (Lane Tech HS) Handout: Radioactive Decay
The half-life of a radioactive element is defined as the time required for half of the atoms in question to decay. For example, the unstable isotope Carbon 14 decays into the stable isotope Carbon 12 with a half-life of 5500 years. [This feature is used for "carbon dating" of wood and wood products, since the fraction of Carbon 14 in the earth's atmosphere is being kept roughly constant by background cosmic rays.] We modeled radioactive decay using red licorice [unstable, radioactive] and black licorice [stable], made by Twizzlers™. We took a full piece of the red licorice, and cut another one successively in halves, which we glued to the paper to indicate the number of atoms present after various half-lives. The graph looked something like this:
Number Left | | | | | | | | | | | |_____|_____|_____|_____. 0 1 2 3 4 Time: Half-livesWe cut the black licorice into pieces to fill in the rest of the column, indicating the number of the new atoms created.
|: Number Left X: Number New | X X X X | X X X X | X X X X | X X X X | | X X X | | X X X | | | X X |_____|_____|_____|_____X 0 1 2 3 4 Time: Half-livesGood, Karlene!
Notes taken by Ben Stark