Atoms and Stars IST 2420 and IST 1990 http://www.is.wayne.edu/drbowen/aasW05

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Atoms and StarsIST 2420 and IST
1990http//www.is.wayne.edu/drbowen/aasW05

• Class 10 March 23

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Midterm Grades

• Grades curved to average of 80, lowest grades get
  boosted most (multiply by .8097, add 19.03)
• (1 95), (2 77), (3 79), (4 68)
• Raw grade in circle, final curved grade in
  square, arrow from raw to final (the one that
  counts)

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77
Raw
Final
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Test-taking Advice

• NEVER leave a question blank
• Exception MAYBE leave a question blank, if wrong
  answers count against you
• Do not get hung up on a few questions so that you
  dont have time for all
• Read test over once before trying to answer at all

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Handouts

• PowerPoint notes
• Final topics (subject to change)
• Information Sheet for Final Exam (subject to
  change)
• Do not expect to get credit for copying
  information from a sheet
• Passbacks

Names

• Initial by your name on signin list

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Science in the News

• The first two actual sighting of planets outside
  the solar system were announced yesterday. These
  two are too hot for life (1500º Fahrenheit)
• Approximately 150 planets known outside our solar
  system. Two methods
• Wobble of star, picked up by wiggles in red shift
• Decrease in brightness when planet passes in
  front
• Both actual sightings from second group
• Used infrared to boost planet relative to star

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Plagiarism

• After tonight, all essays on diskettes
• I believe that I am seeing plagiarism in Essays.
• You should read the section on plagiarism in the
  Syllabus before doing this
• If A copies from B, both are at fault.
• If I cannot tell who did what, I will be
  impartial
• Plagiarism applies to (wrong) ideas as well as
  words

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Readings

• Keplers Three Laws
• Inertia tendency of a body to keep moving in
  same direction and speed if not acted on by a
  force
• Gravitational attraction, e.g. towards sun
• Planetary orbit, ellipse, is compromise between
  these two

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Readings

• Black Holes gravitational force
• Force gets bigger as mass gets larger, distance
  less
• Large enough mass, short distance, escape
  velocity gt c, speed of light

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Readings

• Black Holes gravitational force
• Since nothing can travel that fast, everything
  within that distance is trapped
• (Event horizon)
• Everything torn apart, does not exist as ordinary
  atoms and molecules

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Readings Isaac Newton

• Newton 1642 1717 b to English rural farming
  family, father died before his birth
• Seems to have been an unhappy childhood, mother
  left him with grandparents
• Did not want to go into farming, sent to
  (Aristotelian) Cambridge University 1661 (19 yrs)
• Studied on his own, cutting edge of math, Physics

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Isaac Newton

• 1665 plague struck Cambridge, University closed
  for two years, Newton returned to farm
• 1666 after earlier work developed critical
  advances in mathematics, optics, gravity,
  astronomy
• Returned to Cambridge 1667

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Isaac Newton

• 1672 paper on optics refraction of light,
  bending rays through prism, breaking it up into
  colors, white light is combination of all colors
• Careful experimental work
• Invented reflecting telescope, elected Fellow of
  Royal Society
• Much continuing criticism from Aristotelians and
  Cartesians, shunned publication

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Isaac Newton

• Became professor at Cambridge, required to become
  a priest, fervent student of theology, kept
  unorthodox and heretical views private
• 1675 requirement for priesthood dropped, Newton
  saved from having to resign
• Lifelong interest in alchemy, arcane knowledge,
  secret codes

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Isaac Newton

• Royal Society (and Paris Academy of Sciences)
  new, active (publishing, paid positions, prizes
  very modern)
• More permanent that earlier e.g. state charters
• Also state astronomical observatories, botanical
  gardens
• Much service to government, but Charles II
  ridiculed Royal Society for weighing of air but
  this was actually critical

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Isaac Newton

• 1684 and earlier, thoughts of Keplers Laws and a
  central force discussed in London Edward Haley,
  Robert Hooke, Christopher Wren
• Haley went to Cambridge to ask Newton about the
  orbit of a planet in a 1/r2 force, Newton checked
  notes from 1666 and said it would be an ellipse,
  Haley awestruck

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Isaac Newton

• Later, nine-page note to Haley who then
  encouraged publication, but Newton improved his
  work
• 1687 Royal Society published Newtons Principia
  Mathematica Philosphia Naturalis (Mathematical
  Principles of Natural Philosophy) or just plain
  Principia

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Isaac Newton - Principia

• Newtons three laws of motion
• Inertia bodies in motion remain at rest or in
  straight-line motion unless acted on by an
  outside force
• F ma (not explicit) Force (size and direction),
  mass, acceleration (size and direction)
• For every action, equal and opposite reaction
• If A has force F on B, then B has force F on A

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Isaac Newton - Principia

• Showed Galileos s ? t2 in footnote, for constant
  Force and acceleration
• Uses both calculus and geometry, since no one
  besides Newton yet knew calculus
• Body (planet) orbiting attractive central force
  sweeps out equal areas in equal times (Keplers
  second law) plus reverse (K2 implies central
  force)

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Isaac Newton - Principia

• Also, inverse square law of gravity implies t2 ?
  r3, and reverse
• Shows that motion in a medium does not follow
  these laws, against Descartes theory of forces
  transmitted by vortices
• Treats motion of moon around earth, planets
  around sun, moons of Jupiter and Saturn all
  similar, geocentrism doesnt work
• Connected moons motion with gravity on earth

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Isaac Newton - Principia

• Then new areas for research
• More precise orbits
• Effects of planets on each other (perturbations)
• Shape of earth
• Tides
• Comet orbits (found orbit of 1680 comet)
• In first edition, concludes with alchemy
• Second, ends with praise to God

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Isaac Newton - Principia

• Second, ends with praise to God
• God can be known by His effects on nature
• God as Great Clockmaker
• Acknowledges does not enquire into causes of
  gravity (hypotheses non fingo)
• Not trying to explain everything
• Principia made Newton famous at 44
• Still a recluse
• Breakdown in 1693, perhaps from depression over
  failure of work on alchemy

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Isaac Newton

• Stood up to King James on Catholic faculty,
  rewarded with post when William and Mary of
  Orange overthrew James
• Warden of English Mint
• Also president of Royal Society
• Abused his power in Royal Society when Leibniz
  sued over priority in invention of calculus,
  Newton wrote the report

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Isaac Newton - Opticks

• Today we use Leibnizs notation in calculus
• 1704 published Opticks, proof by experiment
• Light as particles or corpuscles, today we think
  of light more as waves
• Reflections from thin layers like oil film on
  water
• Queries to spark further research
• Ending studying nature reveals our duty to God

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Isaac Newton

• Theology (still hid heretical views) fit with
  ideas of time, he was used to argue for
• Existence of God
• Sacredness of property
• Legitimacy of social hierarchy, duty, enlightened
  self-interest
• Refused rites of Anglican church at death but
  buried at its Westminster Abbey

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Isaac Newton

• Alexander PopeNature, and Natures Laws lay hid
  in Night.God said, Let Newton be! and All was
  Light.
• Revolutionary impact on science
• Precise mathematical laws, numerical predictions
• Causal, with explanatory power (force, mass)
• Mechanical explanations clockwork universe
• Experimental verification
• Model for society American constitution

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Isaac Newton

• Science and technology still largely separate
• More influence of technology on science than the
  reverse
• Some interplay in area of scientific instruments
  improved by science
• Role of alchemy, printing of handbooks of recipes
  and methods for artisans
• Francis Bacon theorist of scientific method

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Isaac Newton

• In 20th century, two explanations for what a
  force is (refers to Nissani article later)
• General Relativity mass bends space-time,
  causing motion like ball bearing on a rubber
  sheet
• Quantum Mechanics forces are due to exchange of
  particles
• Still not combined
• Hierarchical science later explains earlier

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Isaac Newton

• Also in 20th century, limitations on
  applicability of Newtons Laws
• Special Relativity mass increases with speed
• General Relativity bending of space-time
• Quantum Mechanics limits how precise the
  location and speed of a particle can be for
  objects on the atomic scale and smaller

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About Science

• Typical pattern
• Improved measurements (Brahe)
• Phenomenological (without explanatory power)
  theory to connect measurements (Kepler)
• Explanatory theory explains phenomenological
  theory (Newton)

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About Science

• Why did science (as we use the term today)
  develop in Europe, at the time that it did?
• One theory combination of tendencies from
  Medieval religion and technology
• Emphasis of European Christianity on doctrine
  supported by logic (influence of Greek
  philosophers)
• Expansion of commerce and trade, printing of
  reliable commercial methods to train more
  apprentices

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About Science

• Science involves discourse between scientists
  shared language, purpose, methods. Variations
  within fields.
• Study science now by studying scientists
• When a new area is being explored, common for
  consensus to change, even drastically
• Even after things settle down, do not expect 100
  agreement

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Expanding Circles

• So far, disconnected centers of knowledge
• Air and water pressure
• Speed of light
• Falling and sliding objects
• Motions of the planets and stars
• Each area (circle? Blob?) expands
• What happens next?

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Expanding Circles

• Eventually, expanding circles must meet and
  overlap
• Different approaches, theories will not agree
• Possible interactions
• Withdrawal (NOMA in science)
• One wins out over the other
• Compromise
• Synthesis

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Expanding Circles

• Case of Newton (and Kepler) uniting terrestrial
  and celestial mechanics
• New theory
• Each is understood more accurately and causally
• A bonus applies to all motion, calculus,
  applied in technology, model for new science
• Other examples coming up

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Epistemology

• Several times you have asked me Is this
  absolutely true? I tend to hesitate with
  questions like this here is why.
• Epistemology the study of knowledge why do we
  accept things as true?
• Two properties we would like for truth
• Eternal unchanging
• Universal the same everywhere

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Epistemology

• Science flunks eternal
• Scientific truth is provisional subject to
  change
• Religions have problems with universal
• How can different religions differ, if there is
  one truth?
• For science and religion, Galileo agreed with
  modern Catholic doctrine there is one truth
• Reinterpret Bible if it disagrees with accepted
  science

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Common Writing Problems

• Functional grammar
• Rules of grammar have a purpose to transmit
  meaning
• Rules of grammar are always changing
• Different grammars for different groups
• Get too far from the groups grammar and you are
  not understood (must change with changes)
• The further you get from the groups grammar, the
  harder it is to understand you
• Being able to use good standard grammar is like
  dressing well for a job interview

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1 Reason for Writing

• To organize your own thinking

1 Way to Good Writing

• Have something you want to say

More Examples and Details

• www.is.wayne.edu/olgt or The Everyday Writer

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Organization

• Many possibilities for organization
• Historical
• Logical
• Specific to general, or general to specific
• Combination
• Signal transitions from one topic to another
• Paragraphs help here

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Quick-and-Easy Organization

• Write body first
• One you have figured out what you are going to
  say (the Body), write the Introduction and
  Conclusion afterwards
• Body should have general statements and specific
  examples and quotes

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Sentences

• A sentence
• Verb (action)
• Subject (did the action)
• Complete thought
• (starts with capital, period at end)
• (Y/N) Because he hit the ball.
• (Y/N) John hit the ball.

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Sentences

• Is it a sentence? Consider it all by itself.
• Common sentence problem 1
• Sentence fragment something that starts with a
  capital and ends with a period but is not a
  sentence
• Because he hit the ball. John ran to first base.
• Fix by joining to main thought with a comma (,)
• Because he hit the ball, John ran to first base.

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Sentences

• Is it a sentence? Consider it all by itself.
• Common sentence problem 2
• Run-on sentence two or more sentences written
  as one
• John hit the ball he ran to first base.
• Fix by breaking into two sentences
• John hit the ball. He ran to first base.
• Or by joining with semicolon () to show
  causality
• John hit the ball he ran to first base

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Number (singular/plural)

• Both subject and verb have number
• If these are not the same, signals conflict
• Members join the club
• A member joins the club
• One s
• Without a reason, do not change number from
  sentence to sentence
• (Bad) People should take care of their health.
  You should take your vitamins.

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Tense (past, present, future)

• Without a reason, do not change tense from
  sentence to sentence

Citations

• Scientific investigation is not, as many people
  seem to suppose, some kind of modern black art.
  (Huxley, 1)
• Cite the source even if you are paraphrasing

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Punctuation

• Apostrophe ()
• Contraction
• Possession (s or s)
• Some words inherently possessive, no (e.g.
  theirs)
• Never for pluralization
• Lists
• Separate list items with commas (last one is
  optional)
• If any list has a comma inside, separate items
  with semicolon

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Wrong Word

• Some words are commonly confused memorize or
  use list or dictionary
• its Vs its
• whose Vs whos
• their Vs there
• too Vs to
• accept Vs except
• Many, many more

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Lab

• Ellipse, Bottom of Pg 53 through Pg 59
• Use ellipses in book for measurement
• Do tonight in Lab
• Assignments 27 and 28
• Measurements for Assignment 36
• Answer questions data sheet only starts to get
  a D tonight
• Science is more than procedures and
  observations/measurements

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For Next Week

• Reader 30 - 41, 45-60
• Lab Manual Experiment 10, Pp 60 - 63 on Lenses
• Turn in Lab 9A report (including measurement
  accuracy for curved shapes from Lab 9!)

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Future Due Dates

• Essay 2 due April 13
• The Everyday Writer (DIS standard) and writing
  web site http//www.is.wayne.edu/olgt, link to
  Writing Guide
• Last regular class April 20
• Work turned in after this date may not be
  included in regular grade
• April 23 Final Exam

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ISP 3360 break time

• ISP 3340 starts

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ISP 3340

• Essay 1 on Rocks of Ages due Feb 23
• Writing mechanics www.is.wayne.edu/olgt, link to
  Writing Guide
• Essay 2 (4-credit) due March 30
• Other articles on course web site password
  needed
• Pictures for Moodle?
• Tone Smith
• Casondria Walker

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End for ISP 3340