Test 1 - 2024

Bring a calculator and writing instruments. I will provide for you any formulas needed.

Material covered

  • Class notes that we've covered--not including atoms.
  • Labs - graphs, slopes, why warm around equator, seasons (not Temperature)
  • Readings - Collapse: Preview and Montana
  • Homework problems and readings assigned for homework.

Chapter 1 of Hobson - Our place in the universe

  • How the behavior of planets and constellations in the night sky differ.
  • The North Star and latitude.
  • Evidence for a round Earth.
  • Specialness of Zodiac constellations.
  • The remarkable observation that all planets circle the sun in very nearly the same plane (close to the "ecliptic"), and move around the sun in the same direction.
  • Earth's direction of rotation. Apparent rotation of stars in the sky.
  • Describing the positions of things in the sky: elevation angle and azimuthal angle. Relation of these to the "horizon".
  • The Greek model of the solar system, vs our heliocentric model.
  • Explanations for the apparent "retrograde motion" of planets.
  • Galileo's observations of the phases of Venus, and other observations he made with a telescope.
  • Labs 1, 2, 3: Rates of change. Best fit line: slope is *average* rate of change. Units of slope. The reason it's warmer when the sun is directly overhead, the seasons. Consequences of Earth's tilt as it orbits the sun: seasons; some parts (close to the poles) have days when the sun never sets, and days when the sun never rises; The tropic of Cancer and Capricorn.
  • Basic powers of 10 (multiplying and dividing).

Electromagnetic waves / light

  • The E-M spectrum:
    • lower frequency than visible light: Radar, radio, microwaves, infrared (IR)
    • visible light
    • higher frequency than visible light: ultraviolet (UV), x-rays, gamma rays
  • Possible ways (and examples) for light to interact with matter:
    • Transmission
    • Absorption - this causes heating
    • Reflection
  • Connection with the greenhouse effect: Transmission of light through atmosphere -> Absorption of light -> heating up -> hot things give off IR radiation -> atmosphere not so transparent to IR.
  • Natural greenhouse effect
  • Using $\lambda\cdot f = c$: $\lambda$=wavelength, $f$=frequncy (cycles/sec), $c$=speed of the wave.
  • Uses for IR cameras / detection.

Lab activities

  1. Graphing lab: calculating slopes; positive/negative correlations
  2. Why it's warmer at the equator. Angle of light relative to surface.
  3. How Earth's tilt out of its orbital plane leads to seasons.

Collapse

  • Diamond's five+ factors in evaluating risk of collapse:
    1. climate change
    2. hostile neighbors
    3. loss of trade with friendly neighbors
    4. environmental damage / fragility
    5. failure to adapt (human response to crisis).
  • Diamond Ted talk - Vikings in Greenland
  • Montana

Format of the test

  • Mostly multiple choice, multiple answer (more than one true answer), true/false, short answers
  • A small number of open ended questions for you to write about.
  • A slope calculation.
  • Even with multiple choice questions, it's *still* a fine idea to jot a note about how you're solving a problem. Sometimes that can lead to partial credit.
  • Formulas: I'll give you any needed--you don't need to memorize formulas. For this exam: speed ($c$) of a wave is wavelength ($\lambda$) times frequency $$c=\lambda f$$ Slope of a line, which is also the average rate of change: $$\text{slope of a line}=\frac{\Delta y}{\Delta x}.$$