Oracle Tutoring, Campbell River, BC
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parallax:
the phenomenon that the position of an object seems to change as the viewer’s location changes.
Source:
Gilmour, Lorna (ed). Collins Essential Canadian English Dictionary & Thesaurus. Glasgow: HarperCollins, 2006.
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.
Source:
Giancoli, Douglas C. Physics, 5th ed. New Jersey: Prentice Hall, 1998.
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.
Einstein postulated, in his Special Theory of Relativity, that effective mass increases as velocity does, according to
m=mo(1-v2/c2)-0.5
where mo is the rest mass, while c is the speed of light.
The rest mass of an electron is 9.11×10-31kg. If travelling at 80.0% the speed of light, or 0.800c, the electron’s mass will be
m=9.11×10-31(1-(0.800c)2/c2)-0.5
which gives
m=1.52×10-30kg
or 1.67 times its rest mass.
Source:
Giancoli, Douglas C. Physics, 5th ed. New Jersey: Prentice Hall, 1998.
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.
Albedo means loss of incoming radiation due to reflection. Light and heat are examples of radiation (see my previous post).
Regarding Earth’s climate, the albedo effect refers to the idea that sunlight that reflects from Earth doesn’t heat it. The greater Earth’s albedo, the less heat Earth absorbs from the sun. If Earth’s albedo decreases, it will absorb more of the sun’s rays, so will heat up. This is the simple way of applying the albedo effect.
Polar ice caps, covered in white snow, are quite reflective. However, as the ice caps melt, they expose rock and ocean, which are potentially much less reflective. Hence, Earth’s temperature could rise from the melting of the ice caps because of a corresponding reduction of the albedo effect.
Source:
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.
Radiation is electromagnetic energy travelling from its source.
Imagine a radio receiver which you can tune to any frequency. Actual radio station signals will be at the low end, then microwaves, then heat (aka infrared), then visible light. Past visible light is ultraviolet light, then X and gamma rays.
Radiation of higher frequency has higher energy. X and gamma rays have such high energy they can pass through solid objects.
Source:
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.
In physics, stress and strain are related, but have very different meanings. A helpful idea is that stress is imposed on an object, while strain measures its reaction.
Source:
Giancoli, Douglas C. Physics, 5th ed. New Jersey: Prentice Hall, 1998.
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.
able to recover its original shape; able to resist permanent deformation after a distorting force is withdrawn.
Referring to a rubber band, it’s not called elastic because it stretches, but rather, because it tends to regain its original shape after the stretching force is released.
Source:
Giancoli, Douglas C. Physics, 5th ed. New Jersey: Prentice Hall, 1998.
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.
Yesterday I took a glass casserole dish of mac and cheese from the oven. Its baking temp was 177C.
An hour later, most of the mac and cheese had been served from the dish. Moving it, I was surprised how warm it still was to the touch.
Yet, how warm was it? I didn’t have a convenient way of measuring, so I opened a browser tab and found rc.rynryder.com, whose members seem to agree that about 60C is dangerous to touch for more than a second or two.
The casserole dish wasn’t hot; rather, just surprisingly warm. I’d estimate it was about 40C.
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.
Looking out over a lake in Nanaimo on Sunday morning, I saw an exceptional Canada goose swimming apart from the others.
The setting was so tranquil, even distance seemed irrelevant: I felt that, on a whim, I could suddenly scoot down to the water, plunge in, and join the goose if I wanted. Yet, how far away was it, really?
Holding my phone at 20cm, or 200mm, I observed the goose at about one-sixth of my phone’s lens port, which is 7mm across. So, to me, the goose appeared 7/6=1.17mm. Yet, a goose that prosperous would likely be about 60cm, or 600mm, from tail to breast. From optics,
object distance/image distance = object length/image length
Therefore,
d/200 = 600/1.17
Multiplying both sides by 200, we get
d=200(600)/1.17 = 102574mm or about 103m
Source:
Bull, John and John Farrand, Jr. The Audubon Society Field Guide to North American Birds, eastern region. New York: Alfred A. Knopf, 1977.
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.
A meteor is the streak of light you might see in the sky at night, when matter travelling through space enters Earth’s atmosphere.
The rock, or whatever matter arrives, is typically travelling at high speed. The air friction it encounters in the atmosphere heats it up, usually to evaporation – but not always. However, it gets so hot it glows, which is what you observe.
The object itself, arriving in Earth’s atmosphere and glowing, is a meteoroid.
Any part of the meteoroid that lands on Earth’s surface becomes a meteorite. As I understand, meteoroids rarely manage to become meteorites.
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.