Listening Very Closely to Insects

Our summer session of Physics 53 begins Monday with the largest class we have hosted in my 5 years at DUML.  Thirty eight students will begin their study of mechanics and will progress through fluids, mechanical waves, and thermodynamics in five short weeks of intensive study. This brief article seemed appropriate for a first blog entry of the session. First of all, because it combines forces and oscillations, which are two of our principle areas of study. Of course, there are a few insects in and around the wetlands which are so prevalent around our island paradise. I propose listening to the audio files contained in the Clarkson University study while we try to avoid the local bugs. Here’s to a buzz free summer session!

Scientists Listen to Faint Sounds Inside Insects

May 14, 2010

Typical atomic force microscopy set-up
Image via Wikipedia

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–>Scientists Listen to Faint Sounds Inside Insects

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Rendering of a ladybug being recorded by the atomic force microscope (AFM) probe.

(PhysOrg.com) — A team of Clarkson University scientists led by Prof. Igor Sokolov are using atomic force microscopy (AFM) to record sounds emanating from inside living insects like flies, mosquitoes and ladybugs.

// // ACS Video Perspective – Researchers highlight coherent multidimensional spectroscopy – pubs.acs.org/JPhysChemVideo

AFM is one of major scientific tools responsible for the emergence of modern nanotechnology. The unprecedented sensitivity of AFM allowed the Clarkson team to record sub-nano oscillations of very faint amplitude (less than the size of one atom) at high frequencies (up to 1,000 hertz or cycles per second). Previous work in the study of was only done at up to 5 hertz. The sounds are recorded by touching the surface of the bugs with an AFM probe. The study of these sounds may allow researchers to discover unknown features and physiology of insects. Sokolov hopes these discoveries may help in finding solutions to the problems caused by insect pests. “Insects are of general interest not only as the most numerous and diverse group of animals on the planet, but also as highly efficient bio-machines varying greatly in size,” says Sokolov. “Some are major agricultural pests and competitors of humans for crops. Mosquitoes and other insects are important vectors of plant, animal, and human diseases. Also, vast lands of the earth are still underdeveloped because they are occupied by blood-sucking insects.” You can listen to audio files of the internal sounds of mosquitoes, flies, and :   //

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// The Sokolov team’s research is published in the top journal of applied physics, , at http://apl.aip.org/applab/v96/i4/p043701_s1 .The team consisted of Sokolov, who has appointments in Physics, and Chemistry and Biomolecular Science; Maxim Dokukin, a physics postdoctoral fellow; and Nataliia Guz, a physics graduate student; and Sergey Vasilyev, instrumental scientist. The other members of Sokolov’s group, physics graduate students Dmytro Volkov, Ravi Gaikwad, and Shyuzhene Li, work on biosensors, self-assembly of particles, and the study of skin aging.

Provided by Clarkson University

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Holiday Reading for Physheads

So, the final exam for this lovely group of physics 53  DUML physheads is over,  grades have been submitted and students are putting finishing touches on the semester; getting ready to head off for the Holidays.  I can’t help submitting the following story relating to Tiger Woods car accident a short time ago:

A Gripping Read

There’s a physics angle to the Tiger Woods business of last week (that I’d not really been following since I was, thankfully, out of the country during the media blitz).

A physics angle? Really? Surely in my attempts to show the science angle in everyday things I’ve gone too far?

tiger-woodss-car-with-get-002

Well, actually there is. So there was some business with a car crashing and so forth, and there are photos of the interior of the car. There’s a book visible. It’s a physics book! It is John Gribbins’ Get a Grip on Physics, from 1999. tiger-woodss-car-with-get-close

It is out of print now, but apparently its Amazon (USA) sales rank shot from 396,224 to 2,268 over a short period. (For the record, before you ask about the other items in the photos (from Getty images), I’ve heard no news on whether umbrella sales also spiked. Or bottled water sales, for that matter.)

I like this story for lots of reasons, but the main one is that this shows to the general public that a high-profile sports star can find some time and interest to dip into a physics book from time to time. These popular level books are for everyone – not just the so-called geeks. Ordinary people with a range of interests who are interested in dipping into the larger culture that is available. I hope it encourages others to venture into this sort of reading material, without feeling/fearing that they are now going to be labelled a “science geek” for doing so. For all I know it was right next to a copy of a collection of Maya Angelou poems on his bedside table, or an excellent juicy murder-mystery novel, before he grabbed it and dashed for the car. That’s the way science should be – just out there among the other great stuff.

Here’s a Guardian story on it, with more information and some quotes from the pleased author.

I’m off to plant copies of D-Branes in the back seats of various local Hollywood stars, especially the accident prone ones. Hmmmmm, now which holiday parties is Lindsey Lohan going to?

1859 Solar Flare – Wired Science

From Wired Science — an interesting article about a huge solar flare in 1859.

Telegraphs Ran on Electric Air in Crazy 1859 Magnetic Storm

  • By Alexis Madrigal Email Author
  • September 2, 2009  filament_trace_big

On Sept. 2, 1859, at the telegraph office at No. 31 State Street in Boston at 9:30 a.m., the operators’ lines were overflowing with current, so they unplugged the batteries connected to their machines, and kept working using just the electricity coursing through the air.

//

In the wee hours of that night, the most brilliant auroras ever recorded had broken out across the skies of the Earth. People in Havana and Florida reported seeing them. The New York Times ran a 3,000 word feature recording the colorful event in purple prose.

“With this a beautiful tint of pink finally mingled. The clouds of this color were most abundant to the northeast and northwest of the zenith,” the Times wrote. “There they shot across one another, intermingling and deepening until the sky was painfully lurid. There was no figure the imagination could not find portrayed by these instantaneous flashes.”

As if what was happening in the heavens wasn’t enough, the communications infrastructure just beginning to stretch along the eastern seaboard was going haywire from all the electromagnetism.

“We observed the influence upon the lines at the time of commencing business — 8 o’clock — and it continued so strong up to 9 1/2 as to prevent any business from being done, excepting by throwing off the batteries at each end of the line and working by the atmospheric current entirely!” the astonished telegraph operators of Boston wrote in a statement that appeared in The New York Times later that week.

The Boston operator told his Portland, Maine counterpart, “Mine is also disconnected, and we are working with the auroral current. How do you receive my writing?” Portland responded, “Better than with our batteries on,” before finally concluding with Yankee pluck, “Very well. Shall I go ahead with business?”

In terms of the relationship between the Earth and its star, it is probably the weirdest 24-hours on record. People struggled to explain what had happened.

NASA’s David Hathaway, a solar astronomer, said that people in the solar community were beginning to understand that there was a relationship between events on the sun and magnetism on Earth. But that knowledge was not widely disseminated.

Another theory held that auroras were actually atmospheric phenomena, that is to say, weather of a particular type. Proof of various sorts was offered. Auroras apparently had a sound, “the noise of crepitation,” or crackling, that marked them as Earth-bound phenomena. Even weirder explanations arose, like meteorologist Ebenezer Miriam’s hilariously quacky quote in The New York Times.

“The Aurora (electricity discharged from the craters of volcanoes) either dissolves in the atmosphere, and is thus diffused through space or concentrated into a gelatineus[sic] substance forming meteors, called shooting stars,” Miriam wrote. “These meteors dissolve rapidly in atmospheric air, but sometimes reach the earth before dissolving, and resemble thin starch.”

But some scientists were on the right track. Eighteen hours before the storm hit, Richard Carrington, a young but well-respected British astronomer, had been making his daily sunspot observations when he saw two brilliant spots of light. We know now that what he was seeing was the heating up of the surface of the sun beyond its standard fusion-powered temperature of about 5,500 degrees Celsius. The energy to do so came from a magnetic explosion as a distended part of the sun’s magnetic field snapped and reconnected.

“They give off the energy equivalent of about 10 million atomic bombs in the matter of an hour or two,” Hathaway said. “[The 1859] one was special, and it was noticed because it was a white light flare. It actually heated up the surface of the sun well enough to light up the sun.”

Though back then Carrington didn’t know what he was looking at, five years of staring at the sun had taught him that what he was seeing was unprecedented. When in the wee hours of the next night, the skies all over the globe began turning brilliant colors, Carrington knew he was on to something.

“I think that it represents a tipping point in astronomy because for the first time, astronomers had concrete evidence that a force other than gravity could communicate itself across 93 million miles of space,” said Stuart Clark, author of the book The Sun Kings: The Unexpected Tragedy of Richard Carrington and the Tale of How Modern Astronomy Began.

Still, it would be decades before the scientific theory would catch up with the observations. British heavyweights like Lord Kelvin opined that the sun could never deliver the level of energy that had been observed on Earth. Understanding what was happening without understanding how the sun worked or the nature of particles was not exactly easy.

“It’s a great example of where theory and observation don’t match up,” Clark said. “The scientific establishment tends to believe the theory, but it’s usually the other way around, and the observations are correct. You have to build up a critical mass of observations to shift the scientific theory.”

Over time, more and more observations did shift the theory, and the sun was held properly responsible for geomagnetic storms. The technological lesson that electrical equipment could be disturbed was largely forgotten, though.

When a geomagnetic storm hits the Earth, it shakes the Earth’s magnetosphere. As the magnetized plasma pushes the Earth’s magnetic field lines around, currents flow. Those currents have their own magnetic fields and soon, down at the ground, strong electromagnetic forces are in play. In other words, your telegraph can run on “auroral current.”

Geomagnetic storms, though, can have less benign impacts. On August 4, 1972, a Bell Telephone line running from Chicago to San Francisco got knocked out. Bell Labs researchers wanted to find out why, and their findings led them right back to 1859 and the auroral current.

Louis Lanzerotti, now an engineering professor at the New Jersey Institute of Technology, went digging in the Bell Labs library for similar events and explanations. Along with field research, the history became the core of a new approach to building more robust electrical systems.

“We did all this analysis and wrote this paper in ‘74 for the Bell Systems Technical Journal,” Lanzerotti said. “And it really made a helluva of a difference in Bell Systems. They redesigned their power systems.”

The fight to secure the Earth’s technical systems from geomagnetic anomalies continues. Late last year, the National Academies of Science put out a report on severe space weather events. If a storm even approaching 1859 levels were to happen again, they concluded the damage could range upwards of a $1 trillion, largely because of disruptions to the electrical grid.

The data on how often huge storms occur is scarce. Ice cores are the main evidence we have outside human historical documents. Charged particles can interact with nitrogen in the atmosphere, creating nitrides. The increased concentration of those molecules can be detected by looking at ice cores, which act like a logbook of the atmosphere at a given time. Over the last 500 years of this data, the 1859 event was twice as big as anything else.

Even so, the sun remains a bit of a mystery, particularly these tremendously energetic events. Scientists like Hathaway are able to describe why one geomagnetic storm might be bigger than another based on the details of how it arose, but they are hard pressed to predict when or why a freakishly large storm might arise.

Scientific understanding of how the sun impacts the Earth and its tech-heavy humans isn’t complete, but at least we know when it got its start: the early hours of September 2, 1859.

“It’s at that point we realize that these celestial objects affected our technologies and the way we wanted to live our lives,” Stuart said.

And it turns out, our burning hot star still does.

Image: TRACE/NASA

The DUML Open House

Last Saturday — wow, has it been a week already? — the Duke Marine Lab hosted an open house and invited folks from the community in to see what we do. This provided a great opportunity to pull out a few of our physics demos and some lab equipment. I decided to run three stations, a hair-raising Van de Graaff generator, a torque and angular momentum stool and bicycle wheel, and an EKG station.

EKG
EKG

Bob reaches a high potential
Bob reaches a high potential

We had a great time interacting with the community and I want to thank my daughter, Nada, Natalie and Nate [NaNaNa…] for helping to explain the physics at the various stations.

Maxwell’s Equations

Our physics 54 class has now been introduced to all four of Maxwell’s equations. We do not have Maxwell’s correction to Ampere’s Law yet, but man we are close. Our current version of these really beautiful equations:
Gauss’s Law for Electricity
\oint_S \vec{E} \cdot \hat{n} dA = \frac{1}{\epsilon_o}\int_{V/S} \rho_e dV

Gauss’s Law for Magnetism[experimentally — no magnetic monopoles]
\oint_S \vec{B} \cdot \hat{n} dA = {\mu_o}\int_{V/S} \rho_m dV = 0

Ampere’s Law [not yet fixed]
\oint_C \vec{B} \cdot  d\vec{l} = {\mu_o}\int_{S/C}  \vec{J}_e \cdot \hat{n} dA = \mu_o I_{thru C}

Faraday’s Law [the negative sign indicates Lenz’ Law]
\oint_C \vec{E} \cdot  d\vec{l} = - \frac{d}{dt}\int_{S/C} \vec{B} \cdot \hat{n} dA

Maxwell's Equations in a proper setting
Maxwell's Equations in a proper setting

Problem Set Format

Since Dr. Brown has asked me to grade your homework and has encouraged you to submit works of art, I suggest a format which will make me very happy and will help you to clearly present your work. While this is not a required format, it will make it easier for me to look at your works of problem solving art.

Given: Restate the problem situation, sketch pictures to illustrate the problem, define variables as needed, etc.

Find: Clearly state what it is that you are supposed to find

Plan: List primary physics principles and laws which apply, any assumptions you make and then suggest how you plan to use these to attack the problem

Calculate: Clearly carry out the necessary calculations, algebra and calculus

Solution: Clearly state the solution — generally a sentence with appropriate numbers or formulaic results