Measurement Notes

TODO: add range, mean, etc.
 heights. Alcohol (ethanol) thermometer, in 10 units. 
1" = 2.54 cm;
1"2 = 2.542 = 6.45
8.5"=21.59cm
11.0"=27.84cm
bargraph=compare
  • Surface area
  • kilograms2pounds
  • Water cohesion/adhesion: capillary action due to electrostatic (van der Waals) forces. Meniscus formed by adhesion of water to negatively charged oxygen atoms in glass.
  • Hindu 500 AD invented zero.
  • 3 tsp (4 in Australia) = 1 tblsp; 8 fl oz (237 ml, 250 in Australia, NZ, Canada) = 1 cup
  • Metric system: French Academy of Sciences after the French Revolution (250,000 units of measurement under the monarchy). Enlightenment: science, logic, mathematics. Units: International System of Units (SI): first prototype meter kept at BIPM was short by 0.2 millimeters: miscalculated flattening of earth due to rotation. Picard 1655 astronomer measured length of a degree of longitude. Delambre and Mechain: 1792 measured the arc of a meridian from Dunkirk to Barcelona. meter=1/10 millionth distance from pole to equator through Paris.
    1983: light in vacuum 299,792,458 meters.
  • 10 trillion cells (p. 106); 10 million olfactory receptors. Average hair cell is 10 um - total 10**8 m long = 100K km. Earth circumference 40K km: 2.5 times around. Moon 384K km, Sun 150M km.
  • Start as egg (zygote) in uterus. "Chicken or the egg" question misses the point: zygote is the start of the chicken, before the egg, there was no chicken, there was mother hen, father rooster.
    • Index Peter Chen