I like Humor. I caught this on on http://www.th.physik.uni-frankfurt.de/~jr/cartoon.html

Science: A Way of Knowing

Physics 101

Physical Science

Be sure to try this: http://dingo.care2.com/cards/flash/5409/galaxy.swf

Chapter 1. The World Around You. Objects and Properties

• Concepts. Generalized mental images of objects or about intangible things.– Imagine that you have

discovered a meteorite in your back yard. A rock that you have never before seen. You are convinced that it must be of extra-terrestrial origin.

– Describe this rock in a telegraph message to someone in the time frame of the 19th century.

– Now describe this rock as you would do it in the year 2006.

– Now describe this rock as someone from “Star Trek Voyageur” might do it! In actuality we probably have the technology today.

In all cases, you would probably describe the characteristics or properties of the rock. You would probably use referents.

Local Scientist Discovers Mushroom Growing in Front Yard

In the Spring of 2001 I discovered this mushroom while mowing the front lawn. I immediately photographed it with my digital camera and emailed a “jpeg” picture to my friend.

The use of Measurement is important in the Scientific Process

• The technique of measurement compares a property to a well defined referent.

• The concept of length is a simple example of applying a referent.

• If I am going to measure my back yard what should my referent be? Metric System1?

• If I am going to measure the size of a carbon atom what should my referent be?

• The value of the property is determined by counting the number of referent units.

• Although we probably have learned the English system in our minds, the Metric system is probably better.

• Typically Realtors use feet.

• Whoops! I can’t use feet here. I would be better off in metric with nanometers.

• For example the size of a hydrogen atom is about 0.5 nanometers.

A teacher never stops learning. I just learned from Table 1.1 that a “jigger” is 2 mouthfuls. Now, on every occasion I will mix a drink for my friends at a party I will probably say “Do you want two or four mouthfuls!”

1The metric system was established by the French Academy of Sciences in 1791.

Time – What really is time?

• The M.K.S. unit of time is the second which was originally defined as 1/86,400 of a solar day. But this is not practical since the earth’s rotation is slowing down ever so minutely over time. Thus we need a better standard for time.

• Our current standard today is an atomic clock—the cesium beam clock in which the second is defined to be exactly 9,192,631,770 periods of a specified radiation from a uniform collection of cesium atoms.

• Your crystal controlled watch is probably good to within a couple of seconds a year.

• My 1904 Waltham pocket watch is probably only good to with 2 minutes a week. But I just like old watches and I like to constantly fiddle with it.

Ballpark Estimations

• Scientists are always doing ballpark or order of magnitude guesses.

• One day at breakfast with my friends the question came up as to how much volume would a mole of grasshoppers ( 6.02 x 1023 ) occupy.

• I actually worked it out on a napkin without a calculator by knowing the earth’s diameter (8,000 miles) and estimating a grasshopper’s dimensions as a cylinder 1 ½ inches long and 3/8 inch wide.

• As I remember it comes out to a few feet all around the earth Thick!

The Scientific Method

“Science is best defined as a careful, disciplined, logical search for knowledge about any and all aspects of the universe, obtained by examination of the best available evidence and always subject to correction and improvement upon discovery of better evidence. What's left is magic. And it doesn't work. –”

James Randi

It took a long while to determine how is the world better investigated. One way is to just talk about it (for example Aristotle, the Greek philosopher, stated that males and females have different number of teeth, without bothering to check; he then provided long arguments as to why this is the way things ought to be). This method is unreliable: arguments cannot determine whether a statement is correct, this requires proofs1.

A better approach is to do experiments and perform careful observations.1http://phyun5.ucr.edu/~wudka/Physics7/Notes_www/node5.html

Many years ago in a Physics 101 class I took a photo of a ball being dropped while being flashed with a strobe light

Ignore these (bounceback)

My hypothesis was that object fall on the earth’s surface as the square as the time

Meter stick

I then performed an experiment to test this hypothesis

I used a polaroid camera (today you could use a digital camera)

time (units) Time^2 Dist. (m)

0 0 -0.08

1 1 -0.07

2 4 -0.05

3 9 0

4 16 0.055

5 25 0.115

6 36 0.2

7 49 0.285

8 64 0.39

9 81 0.52

10 100 0.65

11 121 0.795

y = 0.0072x - 0.07

R2 = 0.9994

-0.2

0

0.2

0.4

0.6

0.8

1

0 50 100 150

Time (units)

Dis

tan

ce

(m

_

http://www.randi.org/research/

At JREF, we offer a one-million-dollar prize to anyone who can show, under proper observing conditions, evidence of any paranormal, supernatural, or occult power or event. The prize is in the form of negotiable bonds held in a special investment account. The JREF does not involve itself in the testing procedure, other than helping to design the protocol and approving the conditions under which a test will take place. All tests are designed with the participation and approval of the applicant. In most cases, the applicant will be asked to perform a relatively simple preliminary test of the claim, which if successful, will be followed by the formal test. Preliminary tests are usually conducted by associates of the JREF at the site where the applicant lives. Upon success in the preliminary testing process, the "applicant" becomes a "claimant."

To date, no one has ever passed the preliminary tests.

HYPOTHESIS AND THEORY

• Once we have summarized experimental and observational results we can form a hypothesis (tentative educational guess) about dropping ping pong balls

• After observing many ping pong balls in such manner and analyzing data we might establish a theory (or law)

• Predictions are always tested• Every law of nature is subject to change based on

new observations• Scientific Results must be reproducible

Pseudoscience

• Astrology is an example of a pseudoscience• Why do scientists reject astrology?• Ans: It just doesn’t work.• Daily Overview: August 26, 2008 • SCORPIO• October 23 - November 21•

You are living your dreams -- in more ways than one! It's a really good time to exert your power in some new way that feels more satisfying and leads to more intriguing developments in the real world.

Branches of Science

• Physics (Mechanics, Energy, Forces, Heat, Sound, Electromagnetics, Nuclear)

• Chemistry• Astrophysics• Geology

• Biology• Biophysics• Nanoscience• Zoology• Botany• Molecular Biology

Some Important Research Laboratories in the United States1

1From Physics Matters (Trefil)

From “Physics Matters” by Trefil/Hazen

Tax dollars can go into either basic research or applied research

GO TO http://www.nsf.gov/statistics/infbrief/nsf08303/ for more information