02 SEP 2016 by ideonexus
Teaching Temperature
Outside Temperatures. Place a thermometer outside a window so students can make daily calculations and keep a chart reporting the actual temperature and the temperature change from the previous day. Students will see that the change can be a negative number without the temperature falling below 0—an often-confusing concept that is clarified by these observations.
An achievable-challenge extension could include barometers, and students who need more advanced work can learn how negative—or...
1 30 JAN 2015 by ideonexus
The Sensation of Pressure
We feel pressure on our skin, when we place our hand over the outlet of
a bicycle pump, for example, as a kind of springy push. Actually,
pressure is the summed bombardments of thousands of molecules of air,
whizzing about in random directions (as opposed to a wind, where the
molecules predominantly flow in one particular direction). If you hold
your palm up to a high wind you feel the equivalent of pressure -
bombardment of molecules. The molecules in a confined space, say, the
interior of a... 1 
notes
notes24 JAN 2015 by ideonexus
Life Favors a Cold, Expanding Universe
If, on the other hand, we live in an open universe, infinite in space and time and continuing to expand into a future without end, then life has to face a prospect of slow freezing {111} rather than quick frying. The universe grows constantly colder as it expands, and the supply of free energy is constantly dwindling. To many people this future of endless ice has seemed even more dismal than the future of cataclysmic fire. But the laws of cosmic ecology put these futures into a very differe... 1 notes
notes21 JAN 2014 by ideonexus
Hell Must be Isothermal
.. . hell must be isothermal, for otherwise the resident engineers and physical chemists (of which there must be some) could set up a heat engine to run a refrigerator to cool off a portion of their surroundings to any desired temperature. Folksonomies: thermodynamics
Folksonomies: thermodynamics
1 notes
notesFunny.
18 NOV 2013 by ideonexus
An Example of the Joy of Hard Science Fiction
If they are going to sink below, then the pressure on the vessel is going to rise as Verne talked about in 20,000 Leagues Under the Sea. If the pressure on the vessel is going to rise, then it's going to collapse unless the pressure within the vessel rises. So the captain is slowly letting the vessel sink into the Moon dust, while the crew is not letting onto the tourists that anything is wrong, but the pressure is slowly going up.
Now just as we don't typically notice the pressure go up or ...This example from a Clarke novel illustrates the fun of Hard-SF in how it leaves it up to the reader to figure things out from their scientific literacy.
07 OCT 2013 by ideonexus
Heat is a Substance
We recognize in the concept of heat which appears
here a similarity to other physical concepts. Heat is,
according to our view, a substance, such as mass in
mechanics. Its quantity may change or not, like money
put aside in a safe or spent. The amount of money in a
safe will remain unchanged so long as the safe remains
locked, and so will the amounts of mass and heat in an
isolated body. The ideal thermos flask is analogous to
such a safe. Furthermore, just as the mass of an iso-
lat...Folksonomies: heat quantification
Folksonomies: heat quantification
1 notes
notesLike mass. It is a quantity.
07 OCT 2013 by ideonexus
Understanding Heat and Temperature
Our sense of touch tells us quite definitely that one
body is hot and another cold. But this is a purely quali-
tative criterion, not sufficient for a quantitative descrip-
tion and sometimes even ambiguous. This is shown by
a well-known experiment: we have three vessels con-
taining, respectively, cold, warm and hot water. If we
dip one hand into the cold water and the other into the
hot, we receive a message from the first that it is cold
and from the second that it is hot. If we th... 1 notes
notesAn excellent description of the distinction between the two.
29 SEP 2013 by ideonexus
The World is a Function
Kakeru Seki: A fact is somehow related to another fact. Unless you understand these relationships, you won't be a real reporter.
Noriko Hikima: True journalism!
Kakeru Seki: Well, you majored in the humanities.
Noriko Hikima: Yes! That's true--I've studied literature since I was in high school.
Kakeru Seki: You havea lot of catching up to do, then. Let's begin with functions.
Noriko Hikima: Fu...functions? Math? What?
Kakeru Seki: When one thing changes, it influences another thing. A ... 1 notes
notesAs a programmer I know that algorithms can relate to the real world, and since these algorithms are constructed in computers that ultimately run on bits and boolean logic, then the real world may be imagined to deconstruct to pure mathematics.
12 APR 2013 by ideonexus
Origin of the National Weather Service
The public at large became more interested in weather forecasting after the Schoolhouse Blizzard of January 1888. On January 12 that year, initially a relatively warm day in the Great Plains, the temperature dropped almost 30 degrees in a matter of a few hours and a blinding snowstorm came.26 Hundreds of children, leaving school and caught unaware as the blizzard hit, died of hypothermia on their way home. As crude as early weather forecasts were, it was hoped that they might at least be able... 1 notes
notesIn 1888 when a sudden snowstorm on a warm day killed hundreds of school children on their way home.
19 JAN 2013 by ideonexus
Climate Change Science is Based on an 1896 Paper
Our understanding that increasing carbon dioxide levels in the atmosphere could change the climate is not new. The relationship between carbon dioxide, water vapor, and climate was first laid out in detail in 1896 by the Swedish physicist Svante Arrhenius, who estimated that a doubling of carbon dioxide levels would cause global warming of 4.9° to 6.1°C. In his landmark paper, Arrhenius reported that "a simple calculation shows that the temperature in the arctic regions would rise about 8°...Reference to the original paper that started Climate Change Science.
