Physics-Related Videos
The following are videos of general interest to physics
majors and science students. Enjoy!
- One-Minute
physics, amusing cartoon animations of interesting physics.
- Physics
for the 21st Century, set of 11 videos about current
frontiers of physics. Two of our Physics faculty appear in
these videos, Professor Mark Kruse appears in Unit 1
(searching for the Higgs particle at the Fermilab Tevatron)
and Professor Ayana Arce appears in Unit 2 (about the
Large Hadron Collider).
- How
to tell if an egg is boiled or raw. Why is this useful
illustration of inertia not taught to everyone in elementary
school?
- In
Search of Giants with ex-pop musician and physicist Brian Cox.
- Magnetic
levitation of a living frog in a solenoid that generates
a 16 tesla magnetic field. A nice discussion of the
science behind the levitating frog is
given here
and involves the concept
of diamagnetism
a weak repulsion that any material object feels when pushed
into a magnetic field.
Note: One tesla is about 10,000 times stronger than the
Earth's magnetic field at sea level so a 16 T field is
strong indeed. In fact, this field strength would quench a
superconductor so one has to use a solenoid build out of
"ordinary" metal to generate such a strong field. Can you
figure out what it would take to float a 65 kg Duke
student via diamagnetism?
-
Inner
Life of a Cell. Although this simulation is perhaps more
well known to biologists as an illustration of the
extraordinary complexity of a living cell, it is full of
interesting examples of equilibrium and nonequilibrium
phenomena of interest to physics students. Examples shown in
the video include: self-assembly of microtubules, kinesin
motors that transport vesicles along microtubule railways,
transcription of DNA followed by translation into proteins,
diffusion of intramembrane proteins in a liquid lipid
bilayer, and so on. Most of what is shown in this movie is
poorly understood, there are many interesting open questions
to explore.
- Homemade
Spacecraft: a video from a simple home-brewed device
consisting of a thermally insulated video recorder attached
to a weather balloon, with a cellphone included to indicate
the GPS location of the device.
- Feynman:
- Feynman
video lectures on the character of physical law. Richard Feynman
was one of the great theoretical physicists of the 20th century
and a great expositor of physics. In the 1960s, he gave several
popular public lectures about physics at Cornell University that later
turned into a book The Character of Physical Law. You may
especially enjoy the sixth lecture about the quantum mechanical view
of nature.
- Fun To
Imagine, some videos of Feynman explaining science to a television
audience.
- The current (2010-2011) television
series Through
the Wormhole, narrated by Morgan Freeman, has numerous
physics-related themes that you will likely enjoy: time
travel, black holes, and antimatter are several examples.
- What
happens when you stick your hand into the high-energy
(7 TeV) proton beam of the Large Hadron Collider?
Several physicists at the Large Hadron Collider were asked
this question, a partial summary of their answers is given
in the video. Note that even for experts, it take some
careful thinking and calculation to answer a seemingly
simple question.
This related
website discusses an actual related example that
occurred when, in 1978, a graduate student accidently
put his head in the path of a proton beam from the U-70
particle accelerator in Russia. This was the world's most
powerful accelerator in 1967, with a maximum beam of energy
of about one percent the energy of the LHC. Remarkably, the
student survived the experience.
-
Duke's Society
of Physics Students likes to hold a liquid nitrogen
party once each semester for all interested students. Here
are some videos of fun things you can do with liquid
nitrogen:
- Make
a liquid
nitrogen bomb by dropping a large plastic soda bottle
filled with liquid nitrogen into a trash can filled with
warm water. (Searching for "liquid nitrogen bomb"
on YouTube will lead
to many similar videos.
The physics? This is the ideal gas law PV=NkT
at work. At room temperature (T~300 K), the
liquid nitrogen initially at about 70 K in the bottle
warms up and turns into a lot of gas (the gas is about 600
times less dense than the liquid). The large amount of gas
in a small volume V creates a large
pressure P=NkT/V that exceeds the material
strength of the plastic bottle and causes the explosion. (Can
you figure out where the bottle breaks first as
internal pressure increases?)
- Magnetic
levitation by a ceramic material (the black block
sitting in liquid nitrogen) that becomes superconducting at
liquid nitrogen temperatures. A strong magnet (the shiny
cylinder) placed over the block starts to descend by gravity
but before it can move an observable distance, its descent
induces powerful eddy currents in the superconductor that
create an opposing magnetic field that suspends the magnet
in the air. Once the superconductor warms up (after all the
liquid nitrogen evaporates away), the eddy current
disappears and the magnet lowers itself gently to the
ground.
Note: This magnetic levitation via a superconductor is
similar to the levitation by diamagnetic repulsion of a frog
mentioned above.
- Shatter a flower.
-
Put your hand in liquid nitrogen (and pull out quickly!)
without harm This is possible because of something
called
the Leidenfrost
effect, in which vapor, produced by boiling at the edge
of a liquid in contact with a hot surface, insulates the
bulk liquid.
Warning: please be very careful if you try this
yourself, do not leave any part of your body in contact with
liquid nitrogen except for a brief moment of time.
- Mad Science videos
related to Theodore Gray's book Mad Science: Experiments
You Can Do at Home--But Probably Shouldn't. One of my
favorites (and something to do at an SPS meeting) is
to Trap
Lightning in a Block.
- Cloud
chamber that reveals the passage of invisible high
energy subatomic particles moving through the air. Many
science museums have a big cloud chamber: a dark box with
what looks like a fine mist falling, with white vapor trails
that appear randomly when a rapidly moving charged particle
like a muon or proton (cosmic ray) passes through the fog.
(The particles could also come from some radioactive source
placed in the chamber.) As a charged particle moves through
the supersaturated alcohol vapor, it ionizes alcohol
molecules which then triggers local condensation of the gas
into a small liquid droplet, which then scatters light and
is visible as a white spot. The group of spots along the
trail is basically a small linear artificial cloud, hence
the name "cloud chamber".
Cloud chambers are easy to build and great fun. You are
welcome to set up and try the commercially made cloud
chamber in the Physics Demo room.
- Acoustic
levitation of an object by using strong sound waves. A
friendly explanation is
given here.
- The
Pale Blue Dot, Carl Sagan rather famous video in which
he philosophizes about how the great scale of the solar
system and universe should help put human social problems in
perspective.
- A
Cosmic Dawn, jazzed up and inspirational musical video
of Carl Sagan and his view of the universe, from
the Symphony of Science.
- J. Robert
Oppenheimer reminiscing about the detonation of the atomic bomb.