Some Misc' Introductory notes on Physics

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Some Misc. Introductory notes on Physics

• Today we live in a world that revolted against
  superstitions and whims and opinions.
• Somebody said, OH Yeah? Prove it! and that was
  the beginning of science as we know it.
• Anyone can say anything they wish but if there is
  no proof then scientists tend to smile and walk
  away.
• The greatest among the scientists are such as
  Isaac Newton. He will appear on every list of
  the top ten smartest guys who ever lived. BUT,
  in a letter to Robert Hookeyou remember him from
  biology, Newton wrote If I have seen further
  than you it is by standing upon the shoulders of
  giants. He wrote that in 1675. What did he mean
  by that?
• Get your team together and see if you can find
  out what he meant by that and to whom might he be
  referring? Be specific in a fine ESSAY (5
  paragraph minimum) for 30 points due_________?

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Galileo

• Galileo was his first namewhat was his last
  name? 5points, write it on a piece of paper for
  EC
• Galileo said the book of nature was written in
  the language of MATH.
• Galileo said only quantitative, objective
  characteristics mattered.
• All mechanics can be quantified.
• Galileo said such as color, taste, odor, the
  senses are not primary qualities but are
  secondary qualities in that they rely on
  consciousness.
• Get your team together and in a 5 paragraph ESSAY
  tell me 3 clear contributions Galileo made to
  science. 30 points. Due_________

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DESCARTES

• This man was a great contributor to scientific
  thought andMATH!
• Ask a math teacher to tell you ONE thing Rene
  Descartes contributed. Bring it back to me on
  paper for 5 points EC
• I will tell younot for ECthat Descartes said
  that Physics was the science of moving forms of
  space just as geometry was the science of the
  resting forms of space.
• He also said that objective nature consisted ONLY
  of the math aspects of objects like size, shape,
  quantity.
• He also went on to say that all mechanics was
  capable of being imitated in a mechanical
  modeliethere was no difference between a
  working clock and a growing trees.
• I would like you to approach your math teachers
  with such ideas and see if they will share their
  opinions of such statements with you. You may put
  that into your next 5 paragraph essayone per
  team30 points. Due_____
• Descartes formulated the first clear statement of
  the Law of Inertia by suggesting that the natural
  motion of an isolated body is in a straight line
  at constant speed, any departure must be result
  of a push or pull.
• He never fully developed this notion into the
  language of sciencemath.
• Your essay should be an interesting reflection of
  your math teachers opinions, ideas, information
  about Descartes.

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The Greeks

• Newton, Galileo, Descartes were a long way from
  the much earlier Greeks like Aristotle whose
  OPINIONS were taken as absolute truth!
• Aristotle was wrong when he said that all motion
  was governed by the objects final aim or
  purpose. A body would move as a result of an urge
  or desire on the part of a mover.
• He also said that objects have a natural realm
  they try to return toso a rock falls down to
  its earthly realm.
• He also was wrong when he said that stillness was
  a desired conditionhence things stopped moving.

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Newtonian Motion

• We bought Aristotles opinions for a long time.
• But Newton proved that motion is neither
  intuitive nor purposeful, there is no inherent
  logic within the object to fill some cosmic
  schemethere is no desire
• Motion simply IS.
• The object has no thought or purpose.
• The Law of Inertia simply states what isnot why.
• Newton taught us there is NO significant
  difference between an object sitting still and an
  object moving relative to some frame of reference
  of our choosing.
• Like may laws of Physics, they seem
  counterintuitive to our common sense.

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Lest we become too arrogant

• Math is truly wonderful for science and it has
  its place in logic BUTMath cannot help us much
  when we try to understand the Aesthetic, the
  Philosophical, the meaningful, humanistic, our
  rational sense of beingand love.or patriotism!
  Icons are not equations, not scientific but they
  speak to some part of us.
• The myth may fail us as accurate, verifiable in
  its description of the way the universe works but
  myths score higher in adding meaning and
  significance to human life.

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A myth

• A myth is a wonderful explanation of something we
  may not understand scientifically.
• You have read myths in your language arts
  classes.
• Get your team together.
• 1. Choose a myth.
• 2. Write a brief summary of it for me.
• 3. CLEARLY point out what scientific principle
  the myth seeks to explain. Include any role
  played by humans in the creation of the
  scientific phenomena in your myth.
• 30 points, one per teamdue_________

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Newtons synthesis

• About 320 years ago Newton, with the
  encouragement of Edmond Halley, published
  Principia Mathematica Philosophiae.
• It is generally believed to be the greatest
  treatise ever published. Therein Isaac Newton
  proposed a new world viewa new universal view.
• It was Mathematical. It wasnt religious or
  emotional. There was no conscious design to
  explain the behavior of nonliving objects.
• These were simple truths, simple LAWS that
  applied to apples as well as to the moon, to the
  planets, to the stars, to childs toys.

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Johannes Kepler

• This man is a study in courage.
• He had to discard much of what he had always been
  taught was true.
• He had to call into question his religious
  beliefs and training.
• He had to decide to CHOOSE math, quantification,
  numbers and logic and what can be measurednot
  felt or thought to be the case.but what indeed
  DID exist and was measurable!

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Keplers Laws

• Kepler looked at the sky at the stars and
  planets. Religion told himhe was studying to be
  a Lutheran ministerthat Heaven was perfection
  and Earth was corrupt.
• The circle was perfect
• Everything, therefore, that moved in the heavens
  above, moved in circular orbits.
• Everyone KNEW this to be true
• No one ever measured it, checked it out, verified
  it though.

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Tycho Brahe

• At the time Kepler was looking up at the night
  sky, so was a little fellow named Tycho Brahe. He
  was a dreadful fellowhe was a drinker, a drunk
  actually, he was a cad and a womanizer and
  generally a party animal.
• BUT
• He had a passion. Every night of his adult life
  he went out to his astronomically outfitted
  backyard and he measured, tracked, recorded the
  motion of every object he could see clearly in
  the night sky. NO TELESCOPE! Not invented yet.
• But he tracked the motion of night sky objects
  across his homemade grid instrumentation and then
  he wrote down that the object was so many degrees
  N,S,E,W of frames of reference of his design.
• He ended up with notebooks FULL of numbers and
  positions.

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Opposites dont always attract

• So here we had a deeply religious Kepler trying
  to understand the behavior of sky objects and the
  wild man Brahe who jotted down columns and rows
  of numbers describing the positions of sky
  objects.
• Tycho Brahe had the data, Kepler needed the data
  to draw his conclusions as to HOW sky objects
  move.
• They met. Brahe, who wore a silver nose since his
  own nose had been either bitten off or cut off in
  a drunken brawl, tantalized Kepler with his
  notebooks but would not give them up.
• Brahe died. Some say of a burst bladder others
  say he died of peritonitis. Now Kepler was
  delayed again in trying to get at those numbers.
• FINALLY the family allowed him the notebooks.

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Keplers Dilemma

• He went to work, Johannes Kepler, pored over
  those notebooks and tried to come up with ways
  the planets moved that allowed them to move in
  circlesPERFECT circlesreligiously correct
  circles!
• BUTno matter what he tried, Brahes numbers and
  perfect cirles did not fit one another!
• So, Kepler had to choose religion or trust the
  numbers written by the sinner Brahe.
• It was truly courageous. Kepler chose the
  calculations made my Brahe. He chose the
  emotionless, measurable numbers. It was wrenching
  for him!

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Keplers Laws of Planetary Motion

• The results of Keplers work are as follows
• Planets travel around the sun in ELLIPTICAL
  orbits with the sun at one foci. This means that
  the planets are sometimes closer to the sun and
  sometimes farther from the sun. When they are
  closer, the planets move faster along their path.
  When they are farther they slow down as they
  travel along their path. BUT the areas swept out
  are always the same for a given time. In
  addition, planets are at varying distances from
  the sun so that closer planets move faster than
  farther planets as they orbit the sun.
• He just didnt know why!! He know what but not
  why. Newton came along to explain why but he
  didnt know HOWit took Einstein to teach us HOW.

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Newton said

• If planets were isolated bodies in empty space
  they would move uniformly obeying the law of
  inertiamotion continues in a straight line until
  or unless some external net force acts to change
  the behavior.
• BUT planets are not alone. Planets feel the
  effects of the massive sun on their behaviorthe
  force of gravity which bends straight line
  trajectories into elliptical orbits.
• Newton said it is the action of this force which
  is responsible for the departure of planets etc
  from inertial motion.
• But even Newton didnt know HOW it worked

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Along came Einstein

• It took Einstein to explain HOW gravity worked.
• Generally what he suggested was this
• Every bit of mass warps, bends the space around
  it, the same way a bowling ball would warp a
  tautly pulled sheet so that everything rolled
  onto the sheet would fall toward that lowest
  curve in the sheet.
• Every mass warps space..
• If you did not exist within the universe, the
  shape of the universe would be different!
• The Earth is the biggest bowling ball rolling
  across the sheet of space. Everything rolled
  onto the sheet close to it will roll down in
  toward the Earth.

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But now

• Good grief
• We still dont know for sure
• There is the chaos theories and the String
  theories and waves theories and the quantum
  theory and and
• We still dont really know for sure. What is a
  force? How does it arise? If we have never
  touched anythingHOW can we cause a change in
  behavior actually!
• SoYOU might need to answer those and MANY more
  questions we still have!!
• Dont ever assume we know everything about
  anything!!!