Last Physics Stories
The
modern electric utility industry in the United States can be traced to the
invention of the practical light bulb in 1879 by
Thomas Alva Edison. Always looking toward the
marketplace, Edison realized that his light bulb would mean nothing unless
he developed an entire electric power system that generated and distributed
electricity. Continue to read from
Emergence of Electrical Utilities in America
More
than anything else, breaking down the light from celestial objects into its
constituent colors has helped us understand the universe. A spectrum can
tell astronomers what an object is made of, how hot it is, how fast it is
moving, and a host of other important attributes.
Read more from pbs
Located
in the Cathedral is the Great Stalactite Organ, the world's largest musical
instrument. Stalactites covering 3 1/2 acres of the surrounding caverns
produce tones of symphonic quality when electronically tapped by
rubber-tipped mallets.
Read more...
Two
species of termites regularly build magnetic mounds. Magnetic mounds,
besides being tall, thin and wedge-shaped with the longer axis orientated
from north to south. To build “magnetic'“mounds the
termites must be able to sense the direction of the earth's magnetic field.
It has been suggested that they do this by means of magnetite in their
tissues....Read
more..... and
Magnetite biomineralization in termites
Alaska
is known as a good place for seeing the polar aurora, also known as
"Northern Lights." Originally the phenomenon was named "Aurora Borealis,"
Latin for "northern dawn," since in the lower 48 states or in mid-Europe it
may appear (on the rare occasions when it does) as a glow on the northern
horizon, as if the sun was rising from the wrong direction.
Read more ...
Before
1820, the only magnetism known was that of iron magnets and of lodestones.
This was changed by a little-known professor of science at the University of
Copenhagen, Denmark, Hans Christian Oersted.
Read more about magnetism and electric current
The
largest superconducting magnet ever built, in the Atlas detector at the Cern
lab, has been powered up successfully. Engineers sent a current of 21,000
Amps round the coils. Atlas will analyse collisions in the
Large Hadron Collider (LHC), which will recreate conditions just after
the Big Bang.
A
few countries are using powerful
electromagnets to develop high-speed
trains, called maglev trains. Maglev is short for magnetic levitation, which
means that these trains will float over a guideway using the basic
principles of magnets to replace the old steel wheel and track trains. ...read
more
At
midmorning August 18, 1894 , citizens of Buffalo NY, saw an image of Toronto
with its harbor and downtown church spires. A side-wheel steamer heading
from Rochester to Toronto was also discernible in this "superior mirage." An
intense temperature inversion caused straight-line light rays to curve
downward over Lake Ontario, creating the mirage. The air over Toronto must
have been perfectly layered and stable to project such clear detail 180km
away,
read more ...
Sharks
also use one sense we don't have at all. The ampullae of Lorenzini give
the shark electrosense. The ampullae consist of small clusters of
electrically sensitive receptor cells positioned under the skin in the
shark's head. Scientists still don't yet understand everything about
these ampullary organs, but they do know the sensors let sharks "see" the
weak electrical fields generated by living organisms. ....read
more
Tsunamis
are unlike wind-generated waves, which many of us may have observed on a
local lake or at a coastal beach, in that they are characterized as
shallow-water waves, with long periods and wave lengths.....a tsunami
travels at about 200 m/s, or over 700 km/hr...read
more
While
our clocks are set by an average 24 hour day for the passage of the Sun from
noon to noon, the Earth rotates on its axis in 23 hours 56 minutes and 4.1
seconds with respect to the rest of the universe. From our perspective here
on Earth, it appears that the entire universe circles us in this time. It is
possible to do some rather simple experiments that demonstrate that it is
really the rotation of the Earth that makes this daily motion occur...read
more about Foucault pendulum and its
physics explanation
The
Laser Interferometer Space Antenna (LISA) will look for gravitational waves
coming from our
Galaxy and other galaxies. LISA will also map the structure of space and
time around black holes and determine if
Einstein's theories are correct. But, what are gravitational waves, how
do we know that they exist, where can we find them, and why should we study
them?
Read from Jet Propulsion Laboratory site
Henry
Lapaut's optical glass company located in Paris, France, made this lens to
be displayed at the 1893 Chicago World's Fair. Captain Schely, Chairmen of
the Light house Board purchased it for use in America. The lens was placed
in the South Tower of Twin Light House Navesnik NJ in June of 1893, and
operated until 1949.
Read more how Fresnel Lens works
Many
people have heard a sonic boom, but few have
seen one. When an airplane travels at a speed faster than sound,
density waves of sound emitted by the plane cannot precede the plane, and so
accumulate in a cone behind the plane. When this
shock wave
passes, a listener hears all at once the sound emitted over a longer period:
a
sonic boom.
Read more
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