How Stuff Works, has recently published a piece outlining the top 10 scientific theories/laws that every human being should know.
I weigh in on the relevance of each of these to everyday life, and I'll add some of my own that they seem to have missed.
10) The Big Bang
9) Hubble's Law of Cosmic Expansion
For these two, see my post on Wilslson and Penzias's discovery of cosmic background microwave radiation in 1965: http://mikeborg-mikepedia.blogspot.com/2011/03/mikepedia-fact-4-1-of-static-on-your.html. These are very important theories to understand in everyday life because they have profound implications on one's spiritual beliefs and belief of a God, or gods. Firstly, the universe did not appear out of nothing, and secondly, the universe has evolved by expanding over time. The concept that the universe started somewhere and sometime implies that before the Universe there had to be space and time- two concepts that were once thought to be static, and are now believed to be quite malleable. These are two important theories that should be incorporated into one's theological/spiritual beliefs, regardless of the extent. I caution: God can still exist if these two theories hold true...who do you think created the space and the time?
8) Kepler's Laws of Planetary Motion
This one is actually three laws: a) law of orbits- planets orbit the sun elliptically, b) law of areas- the area between the sun and the earth as the earth moves over a predetermined length of time is always equal, and c) the law of periods- basically that planets orbit the sun in proportion to their distance from the sun.
This third law is probably the most important, in my mind. This sets the groundwork for our understanding that different planets have different year-lengths, and is an important variable in our quest for intelligent life in the universe.
7) Universal Law of Gravitation- this one is quite obvious. As anyone living near the coast can easily see, the tides rise and fall because of the gravitational attraction to the moon.
6) Newton's Laws of Motion- these are probably the most useful of this list in everyday life. I believe that learning these three laws should be a prerequisite to graduating high school- they are integral to understand. Very simply stated:
First Law- objects will maintain a constant velocity (0 can be considered to be constant) unless acted upon by an external force
Second Law- force=mass x acceleration, basically a heavier object will require more force to put into motion at a given acceleration
Third Law- Action-reaction- to every force, there is counter-force (think of a see-saw).
5) Laws of Thermodynamics- These too, are incredibly useful in everyday life. This is the basis of the mantra "calories in=calories out". Basically this refers to the first law, that matter and energy are both conserved and to get one you must expend the other (E=mc^2)
4) Archimedes Buoyancy Principle- The force acting on a submerged, or floating, object is equal to the force of the displacement of water. Thus, if you fill your swimming pool to the top and expect to be able to fit 30-40 people in it...expect to lose quite a bit of water by the time you're done. If you've ever intend on being in a boat, make sure to review this one. As long as the mass of the volume inside the boat is less than (or, in theory, equal to) the mass of the volume of water that could be in the boat, you'll float :)
3) Evolution and Natural Selection- this theory always gets branded as the "humans came from monkeys" theory and is incorrectly positioned counter to the concept of God and Divine creation. It's more than just monkeys and humans, it refers to the change over time in one or more inherited traits within a population. In other words evolution describes the expected change in a gene pool over time given a host of external, and internal, factors (population, predation, environmental aspects, etc). The fact is, it's been used in some way, shape, or form since the late 19th century to describe why there are differences in inheritance between different subpopulations of the same species.
This is also a theory that you should incorporate into your spiritual beliefs- no has ever, reasonably, suggested evolution cannot be the work of God himself. In fact, a popular movement has recently arisen among young Christian scientists that God, in order to preserve his divine creations, would provide a system where they could adapt to changes in the natural world.
2) Theory of general relativity
Ever wonder why commercial airplanes travel in semi-elliptical flight patterns, and not in straight lines? It's because when they take off, the Earth is still moving beneath (called the Coliolis Effect- stay posted for an upcoming piece on this one). This is kind of the same idea- objects in space bend the very fabric of space-time in proportion to their mass and thus appear to orbit each other.
Why is this important to you? This work has led to explanations of black holes (by Stephen Hawking) and the understanding that light from far away stars can be bent by gravitational fields, thus improving our methods of understanding our solar system, galaxy, and universe.
1) Heisenberg's Uncertainty Princple- I don't really see how this is relevent to everyday life, but here goes.
It is impossible to know, with any degree of certainty, both the position and momentum of a particle because of the wave-particle duality: basically, particles can, and do, behave as both a particle and a wave simultaneously. Thus, when we measure the position of a particle, we are treating it as a particle, and when we measure the momentum of a particle, we are treating it as a wave. This understanding has led to, directly or indirectly, major booms in chemisty, physics, high-tech, and nano-tech in the past(at least) 30-40 years.
The theores that How Stuff Works missed:
1) Plate Tectonics- I personally believe that it is much more relvent to everday, ordinary people, to know how Earthquakes, volanoes, and tsunamis work, and to use this information to avoid areas where said events tend to occur periodically, instead of knowing that a particle exists as both a particle and wave...but that's just me.
2) Doppler Effect- see my post on this: http://mikeborg-mikepedia.blogspot.com/2011/03/mikepedia-fact-4-1-of-static-on-your.html. Wouldn't it be nice to know that when a fire truck's siren sharply increases in frequency, you should probably get out of the way? Seems pretty useful to me!
3) The germ theory- how about the idea that disease can often be caused by infectious microorganisms, and not simply by curse or miasma (see Italian explanation for bubonic plague circa ~1200-1300 C.E.). This seems like an important theory to understand when one is prescribed antibiotics with a bacterial infection.
4) Herd Immunity- this refers to the idea that once a significant proportion of a population is vaccinated against an infection disease there is certain level of of protection inferred upon those who possess no immunity. Ie/ in theory, if everyone in your neighborhood is vaccinated against the flu except you, and your neighborhood is a static community where no one enters or exits, you will not get the flu. The point: get your flu shot, you'll be helping society more than you know.
5) Ideal Gas law
6) Cell theory
And the list goes on, and on, and on. The point of the How Stuff Works articles is that non-scientists should educate themselves in scientific theory to an extent, which will ultimately help them understand the world around them.