Transcript Daniel Bernoulli

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.
How A Curve Ball Works
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.
Rudolph Clausius
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.
Electromagnetic Induction
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
Eelectron = energy of emitted electrons
Elight = energy of light striking a metal
• Proved light is
quantized
– He won a noble prize for
this discovery in 1922
Ethreshold = minimum energy necessary
to remove an electron from the metal.
E=
2
mc
• 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.
Albert Einstein in 1912
Albert Einstein later in life
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,butter
milk, 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.
The
Structure of
Diamond,
an Allotrope
of Carbon
Graphite, an Allotrope of Carbon
Buckminsterfullerene, an Allotrope of Carbon
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
specialized
cells such as
blood,
muscle or neural
cells.
Stem cells and
bioengineering
Scientists
Scientist
Accomplishment
Connection
Newton
Universal law of
gravitation
Space travel
Clausius
2nd law of
thermodynamics
Photoelectric
Refrigeration, steam
power and Entropy
Photoelectric effect and
atomic energy
Einstein
E= mc2 = hv
Faraday
Bernoulli
Electromagnetic
induction
Physics of fluids
Electrical generator
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.
• #31
• There contributions to
science and their connection
to technology.
• #1-15 & #31
• What are Luddites and when
and why were they created.
• #16
• George Washington Carvers
contribution to science and
technology.
• #18-19
• Are human entirely
responsible for global
warming?
• #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.
• #26
• What is Genetic
Engineering.
• #29
• What are stem cells and for
what purpose is current
research directed.
• #30
• What fact of quantum
mechanics is used in
quantum cryptography?
• #32