The Conservative Cave
Interests => The Science Club => Topic started by: dutch508 on December 31, 2009, 04:21:28 PM
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I'll start this thread with the basic statement that todays' people are woefully ig'nernt.
I propose we post in this thread information that the members feel should be general knowledge, but somehow are not.
I'll start:
The following laws of physics are considered fundamental, but many of them refer to idealized, closed systems, which are hard to obtain in the real world. Also, some are altered slightly in different circumstances. The laws that Newton developed, for example, are modified by the findings of the theory of relativity, but they are still basically valid in most regular cases that you'll run into.
Newton's Three Laws of Motion:
Sir Isaac Newton developed the Three Laws of Motion, which describe basic rules about how the motion of physical objects change. Newton was able to define the fundamental relationship between the acceleration of an object and the total forces acting upon it.
Three Laws of Motion
1) Newton's First Law of Motion states that in order for the motion of an object to change, a force must act upon it, a concept generally called inertia. (an object in motion remains in motion unless acted upon by an outside source)
2) Newton's Second Law of Motion defines the relationship between acceleration, force, and mass. (http://z.about.com/d/physics/1/G/F/-/-/-/NewtonSecondLaw.jpg)The mathematical formulation of the second law is shown, with F representing the force, m representing the object's mass and a representing the object's acceleration. The sigma symbol to the left of the force indicates that it is the net force, or the sum of all the forces, that we are interested in.
3) Newton's Third Law of Motion states that any time a force acts from one object to another, there is an equal force acting back on the original object. If you pull on a rope, therefore, the rope is pulling back on you as well. (for every action there is an equil and opposite reaction)
"Law" of Gravity:
Newton developed his "Law of Gravity" to explain the attractive force between a pair of masses. In the twentieth century, it became clear that this is not the whole story, as Einstein's theory of general relativity has provided a more comprehensive explanation for the phenomenon of gravity. Still, Newton's law of gravity is an accurate low-energy approximation that works for most of the cases that you'll explore in physics.
Conservation of Mass-Energy:
The total energy in a closed or isolated system is constant, no matter what happens. Another law stated that the mass in an isolated system is constant. When Einstein discovered the relationship E=mc2 (in other words that mass was a manifestation of energy) the law was said to refer to the conservation of mass-energy. The total of both mass and energy is retained, although some may change forms. The ultimate example of this is a nuclear explosion, where mass transforms into energy.
Conservation of Momentum:
The total momentum in a closed or isolated system remains constant. An alternative of this is the law of conservation of angular momentum.
Laws of Thermodynamics:
The laws of thermodynamics are actually specific manifestations of the law of conservation of mass-energy as it relates to thermodynamic processes.
The zeroeth law of thermodynamics makes the notion of temperature possible.
The first law of thermodynamics demonstrates the relationship between internal energy, added heat, and work within a system.
The second law of thermodynamics relates to the natural flow of heat within a closed system.
The third law of thermodynamics states that it is impossible to create a thermodynamic process which is perfectly efficient.
Electrostatic Laws:
Coulomb's law and Gauss's law are formulations of the relationship between electrically charged particles to create electrostatic force and electrostatic fields. The formulas, it turns out, parallel the laws of universal gravitation in structure. There also exist similar laws relating to magnetism and electromagnetism as a whole.
Invariance of the Speed of Light:
Einstein's major insight, which led him to the Theory of Relativity, was the realization that the speed of light in a vacuum is constant and is not measured differently for observers in different inertial frames of reference, unlike all other forms of motion. Some theoretical physicists have conjectured different variable speed of light (VSL) possibilities, but these are highly speculative. Most physicists believe that Einstein was right and the speed of light is constant.
Modern Physics & Physical Laws:
In the realm of relativity and quantum mechanics, scientists have found that these laws still apply, although their interpretation requires some refinement to be applied, resulting in fields such as quantum electronics and quantum gravity. Care should be taken in applying them in these situations.
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Invariance of the Speed of Light:
Einstein's major insight, which led him to the Theory of Relativity, was the realization that the speed of light in a vacuum is constant and is not measured differently for observers in different inertial frames of reference, unlike all other forms of motion. Some theoretical physicists have conjectured different variable speed of light (VSL) possibilities, but these are highly speculative. Most physicists believe that Einstein was right and the speed of light is constant.
Ummm, the theory that the speed of light is a constant is in contention. Einstein may not have been right about that after all.
http://www.sciencedaily.com/releases/1999/10/991005114024.htm
or: http://kottke.org/02/08/speed-light-not-constant
or: http://www.newscientist.com/article/dn6092-speed-of-light-may-have-changed-recently.html
OK, NOW, which of these laws are next to be discredited or changed??
Finally, you didn't even mention Boyle's Law. :wtf2:
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Finally, you didn't even mention Boyle's Law. :wtf2:
Boyle's Law: If you're overweight and homely but can sing, you to can become rich and famous.
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lolol
I can't sing either
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TL;DR
:tongue:
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(http://img269.imageshack.us/img269/3285/their.png)
10 Words You Need To Stop Misspelling (http://theoatmeal.com/comics/misspelling)
Figured I'd start off easy.
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Grocer's apostrophes.
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The problem with threads like this is the people who should read them don't. Or they don't care. Either way, it's a waste of time.
But in the spirit of cooperation in the New Year (forget cooperating by the time March rolls around, mkay?), I offer this:
Rule: Use fewer to describe countable things. Use less to describe uncountable quantities, collective amounts, and degree. These terms are not interchangeable.
If you can substitute much as the modifier, then use less; if you can substitute many, use fewer.
Look at some examples:
# Fewer law suits result in less litigation
# Although sand may be technically countable, no one ever does; hence, the less sand we find in our beach bag, the better.
# The estate is valued at less than a million dollars. (Consider “a million dollars†a collective noun unless you plan to count specific dollar bills.)
This means that you get in the line at the supermarket checkout when you have FEWER than 20 items, not LESS than 20 items.
Grammar Nazi (http://www.llrx.com/columns/grammar2.htm)