High School Physics SMILE Class

16 September 1997

Notes taken by Alex Junievicz

There is another SMILE program in Oregon, but that one is directed at students.

Clovis Price was killed on his way to Canada in an auto accident. He was a Chemistry teacher at Flower Vocational H.S.

Presentation by Pete Insley

[Retired from Whitney Young now at Columbia]

How may images are produced by an object between two mirrors?

Tow mirrors made of mirror tiles (approx $1.00 each at Home Depot; etc) are taped together and set at various angles. How many images are seen?

angle | #Images |

90^{o} |
4 |

60^{o} |
6 |

45^{o} |
8 |

30^{o} |
12 |

Students were asked to draw angles with a protractor and then the mirrors were set on the students sketches and the class was asked to tell what number of images they saw. Next we were asked to predict what was the angle for 5 images....First 75 was predicted, and then someone came up with 72 degrees. She said that the product of angle and number would be 360 degrees...Thus 360/5 = 72 deg.......

Predict .. then .. Test

Next Peter pulled out several squares. He put 3 on the space between
the mirrors set at 90 degrees.

Next Peter pulled out several 2x2 squares. He put the 3 squares in
the space
between
the mirrors set at 90 degrees [90^{o}].

Area | Perimeter |

12 | 16 |

Area = 12

Perimeter = 16

Area = 12

Perimeter = 16

Area = 12

Perimeter = 20

3 squares remain the same but the

perimeter can change. He asked for

predictions then showed answers.

He suggested we think about cubes with three mirrors.

Larry Alofs (Kenwood)

Measuring Density of gas

Equipment: Gas lighter, Graduated cylinder, Water tub, Electronic scale

Instead of measuring the mass of the graduated cylinder, he measured the mass of the lighter before and after expelling the gas into the graduated cylinder over-turned under water. The trick to good results is to have the lighter wet in both measurements...shaking off excess water before each measurement.

mass of lighter before (wetted and shaken to remove water)

Mass 21.49 Vol of gas expended 68ml Mass after 21.33

D = m/v D = .16g/68ml = .0024 g/ml or 2.4 g/l

1 mole =22.4l 2.4g/l times 22.4l = 54 g

After correcting for temperature it came to 59 g

The atomic weight of C_{4}H_{10} is 58 grams/mole

Presentation of Bill Blunk [Joliet Central]

He took a long thin balloon and showed that in throwing it laterally, it would not go any distance, but throwing it oriented along its axis (because of less air resistance) it would go for some distance.

Attila Gorilla Sold by Amazing Toys

319 Central Ave

Great Falls MT 59401

3 for $2.50 1-406-727-5557 Bob Pechlin

Presenter Ann Brandon Joliet West

ISPP is vending laser Pointers for $25.00 With Batteries

Wavelength 670 * 10She had a diffraction grating [http://230nsc1.phy-astr.gsu.edu/hbase/phyopt/grating.html]
of 13,400
lines per inch

Conversion to metric:

1 inch/13,400 * 2.54/1 inch * 1m/100 cm = 1.894*10^{-6}
meters

l = d*x / angle * N {number of
diffraction peak) = 1.894*10^{-6} * 2.25 / 6 * 1 =>710 *10^{-6}
meters