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Sir Isaac Newton
• 1642-1727
• 1665 – discovered Law of Universal Gravitation
• Fgravity = Gm1m2/r 2
– r = distance between two mass centers
– G = constant
– Fgravity = gravitational force
• Technology necessary to place satellites in space and land on the moon.
• Also credited with inventing calculus
Weight and Mass
• Mass is proportional to quantity of matter only.
• Weight is proportional to quantity of matter and gravity.– You may be weightless in
outer space but never massless!
Daniel Bernoulli
• 1700-1782
• 1725 -First blood pressure measurements– 170 years latter modern methods were
developed. However, still used for air speed
Bernoulli’s Fluid Dynamics• (v2/2 )+ P = constant
(Density x velocity2 /2 )+pressure = const.As velocity of fluid increases its pressure
must decrease
An exchange of kinetic energy for pressure
• Latter his principle was used to design the first air plane.
Rudolph Clausius• 1822-1888
• Discovered the second law of thermodynamics
Entropy of universe tends to a maximum
In 1852 informed us “the universe is dying.”
• His principal improved effectiveness of steam engine and refrigeration.– “Heat can never pass from a colder to a warmer body without some
other change, connected therewith, occurring at the same time”
• Latter Maxwell, another scientist defined entropy = disorder (randomness) or chaos
∆S for the universe > 0
2nd Law• Workin = Workout + heat
• Workout < Workin
• Heat flows spontaneously from hot to cold.
• Like your refrigerator. Work or energy is required to flow heat from cold to hot.
• Heat is proportional to particle velocity and randomness or chaos which is Entropy.
Michael Faraday
• 1791-1867
• 1831-Discovered electromagnetic induction– His discovery lead to
electric motor and generator and a whole new concept of energy.
– Change in magnetic field per time is proportional to electric power generated.
James Clerk Maxwell• In 1862 used Faraday’s cell model to derive
his famous Maxwell equations.
• Calculated electro-magnetic waves must travel at light speed. Proving Faraday correct.
• “The Special Theory of Relativity owes its origins to Maxwell’s equations of the electromagnetic field.”
Albert Einstein
Albert Einstein• 1879-1955
• 1905 - Told us the law of the photoelectric effect.
• Basically the law is: Eelectron = Elight - Ethreshold
• Proved light is quantized– He won a noble prize for
this discovery in 1922
Eelectron = energy of emitted electrons
Elight = energy of light striking a metal
Ethreshold = minimum energy necessary to remove an electron from the metal.
E = mc2
• In 1905 Einstein also told us E=mc2
– Energy = mass x light speed squared
– Light speed in vacuum is 3 x 108 m/s !!
– Simple elegant equation relating matter and energy which led to the atomic bomb.
• Einstein’s letters to President F.D.R. in 1939 began the nuclear arms race between US & Germany during WWII.
• 2 gram matter is equivalent in energy to 42.92 ktons of TNT or 3 Hiroshima A-bombs.– Antimatter converts matter into energy on contact.
Luddites• Today people threatened by technology are
called Luddites.
• 1800 – Jacquard’s loom & Ind. Revolution
• 1812 – England at war with U.S.– U.S. trade embargo forced England to supply all its
own textiles.
– Increased need for expensive automated weavers replaced craftsmen by factories.
– Luddites by Richard Conniff, Smithsonian Magazine, March 2011
“General Ned Ludd”• Ned Ludd
– Broke some stocking frames which was seen as heroic by his peers.
– Henceforth, he was blamed for all such mishaps.
• A guerrilla army formed under the name of General Ned Ludd to oppress factories– A secret army which controlled the night
– Demanded restoration of compensation & working conditions
George Washington Carver• Circa 1860-1943 – born of slave parents
• Improved crop rotation with new legume crops– Farmers began planting peanuts, or sweet potato, or soy
beans one year and cotton the next, etc.
– Developed technology to utilize legume crops such as peanut oil, printing inks, synthetic rubber and highway pavements.
• Communicated his scientific findings to poor farmers– 37 agricultural bulletins written over 45 years
– Clear cogent writing style easily understood by uneducated farmer.
G. W. Carver
adhesives, axle grease, bleach,buttermilk, chili sauce, fuel briquettes, ink, instant coffee, linoleum,mayonnaise,
meat tenderizer, metal polish, paper,plastic,pavement,shaving cream, shoe polish, synthetic rubber, talcum powder and woodstain.
Global Warming• We are in a warming phase since the end of the mini
ice age (glaciation), 300 years ago.
• There has been 51 glaciations in the last 2.58 MM years.
• The mean global temperature has increased 1 oC over last hundred years and 0.5 oC since 1980.
• Species adaptation through migration and genetic mutation.
• Deforestation and fossil fuel combustion increasing atmospheric CO2
Causes of Global Warming• There are natural causes
– Planet positioning such as: Axis tilt, eccentricity of Earth’s orbit and precession of vernal equinox
– Solar and planetary changes such as: Volcanic activity and sun spots
• Man’s effect on global warming is believed to be from CO2 emissions. – There is no irrefutable data to directly link humans
to earth’s warming. Nevertheless, 1oC/100years is alarming.
Allotropes
• Carbon and other elements can exist in various forms. These forms are called allotropes.
• Allotropes of carbon are graphite, amorphous, and diamond, and nanotubes. These are macromolecular.
• A molecular allotrope is Buckminsterfulleranes.
Nanotechnology• Nanometer is one billionth (10-9) of a meter
• Nanotechnology is technology on a nanometer scale allowing unique physics of such small particles.
• Extraordinary composite construction materials
• More effective drugs• Atomic size computers• Self replicating Nanorobotics
Gene Splicing
• Cutting a gene from one organism and spliced into DNA of another organism.
• Bacterium can manufacture human insulin when that human gene is spliced into the bacterium’s DNA.
• Peas have been given the gene for weevil resistance from the kidney bean.
Genetic Engineering
• Modifying DNA with genes coded to change organisms characteristics.
• Most used today for engineering crops.
• Long term health effects to consumer from engineered foods is unknown.
• Humulin®
Embryonic Stem Cells
Stem cells can reproduce and differentiate into specializedcells such as blood, muscle or neural cells.
Stem cells and bioengineering
ScientistsScientist Accomplishment Connection
Newton Universal law of gravitation
Space travel
Clausius 2nd law of thermodynamics
Refrigeration, steam power and Entropy
Einstein Photoelectric
E= mc2 = hv
Photoelectric effect and atomic energy
Faraday Electromagnetic induction
Electrical generator
Bernoulli Physics of fluids Air travel
Quantum Mechanics
• Quanta are both particle and wave
• Their exact location is unknown
• If seen or measured they lose wave function.
• The theory of quantum physics triggered the development of modern solid state electronics, lasers, LEDs many others.
• Near future developments include exponentially faster quantum computers and quantum cryptography, ability to detect eavesdropping.
What you should know
• The five great scientist discussed in class.
• There contributions to science and their connection to technology.
• What are Luddites and when and why were they created.
• George Washington Carvers contribution to science and technology.
• Are human entirely responsible for global warming?
• #31
• #1-15 & #31
• #16
• #18-19
• #20-21
What you should know
• Suggest at least two possible causes for our current warming trend.
• What are allotropes and how do carbon allotropes connect to nanotechnology?
• What is gene splicing and what purpose has it been used for.
• #21
• #22-25
• #27-28
What you should know
• Explain nanotechnology and how it’s currently being used. Explain the possibilities of this new technology.
• What is Genetic Engineering.
• What are stem cells and for what purpose is current research directed.
• What fact of quantum mechanics is used in quantum cryptography?
• #26
• #29
• #30
• #32