On November 28 I attended a workshop offered by Dr. Chris Beck (Emory University) and Dr. Larry Blumer (Morehouse College) during the NABT conference in Atlanta, GA. I chose to attend the workshop to learn about an organism that can be used for laboratory investigations.
During the workshop I also realized that working with these organisms, which are easy and relatively inexpensive to culture, would provide the life science teachers at my school with a "system" for collecting large amounts of data that can be used to teach statistical methods and tests. I hope the Bean Beetles turn out to be a good organism to work with!
I invited Dr. Beck and Dr. Blumer to our school to give a brief presentation about the beetles to the life science teachers and our students. I charged the students to review the literature on bean beetles and to come up with three "questions" they would like to investigate. I can't wait to find out what they come up with! Also, the teachers who attended asked some great questions to help them consider ways to use these organisms in their classes.
For very useful information about Bean Beetles, please go to http://www.beanbeetles.org/. This website has been set up by Dr. Beck and Dr. Blumer and is an excellent "go-to" for an introduction. If only someone could "discover" Mendelian characters for these critters - we might all be able to replace fruit flies for some of our genetic experiments!
This year I already have 2, highly motivated students who wanted to replace the fruit fly genetics lab with something that would enable them to ask their own question and find their own answers. Anyone else interested? If so, just find or email/message me (Ms. Allio)
Electrostatics in general is one of the coolest and most fundamental topics in Physics. Almost the entire US technology base, and even the national economy depend on industries built around a deep understanding, and innovative use of electrostatic principles.
Yet somehow, many high school and middle school electrostatics labs have been relegated to simple exercises like rubbing balloons through your hair and moving bits of tissues paper with charged combs. So here, I'd like to supercharge some of these ideas and introduce some opportunities for more science, measurement, and innovation around the topic.
Electrostatic Simulations Let's start with just trying to "see" and understand what is going on in simple electrical situations with charges and fields and voltages, etc. Chalkboard drawings are just so antiquated. Instead, start by playing with these three online simulations by clicking on the links or pictures below.
A 2-dimensional Electrostatics Applet. This one lets you move charges around and plots fields, potential difference (Voltage), equipotential lines. etc. as things move around. The picture above shows the fields, potential, and charge for a quadrupole (two positive and two negative charges).
A 3D Electric Field visualization applet for 2D charge distributions. This picture shows the electric field strength (in the z axis) of a simple dipole (one positive and one negative charge)._
A 3-dimensional Electrostatic Field Applet that let's you look at the fields that result from interesting 3-D charge distributions and simple current configurations. The picture above shows a couple of simple wire loops with current running in opposite directions.
When you get the point that you think you understand what is going on and how to visualize it, try playing this game of Electric Field Hockey and see how you do! You have to place charges on the field to make the puck respond the field generated by your placed charges in order to navigate the boundaries into the goal! Click on the picture or link below to play.
Electrostatics in the Real World Now that you've fiddled with a few spiffy simulations on the computer to begin to get a feel for electrostatics, now how do we translate these ideas to the real world? If I was really old-school, I'd suggest starting by making a simple electroscope and electrophorus with some thin metal foil. Yawn.
(Speaking of old-school, though, this is one of my favorite Electrostatic demos, by Prof. Lewin at MIT demonstrating the magic of cat fur. I've seen it in person, where the flash effect is much more obvious than in the low frame rate video. It's the deadpan theater aspect that really does it for me.)
Okay, yes, cat fur and Styrofoam are really old-school, though evidently fun when properly wielded. But there are a couple of more modern variations like the PVC Pipe Static generator that work REALLY well,
Or how about making a real-life 3-D electric field viewer? (easier than it sounds-the whole thing is doable in about 5 minutes start-to-finish) Try this variation on the traditional magnetic field viewer (simply 1/16th inch slivers of 0000 (ultra-fine) steel wool suspended in baby oil. To see electric fields instead, just substitute 1/16th inch slivers of one of your classmate's black hair. Bonus points to any student who can explain how or why this works. See William Beaty's site for details including a video example.
Better yet, if you'd like to use some of this last century's technology, how about making a REALLY sensitive electronic electrometer? The circuit couldn't be simpler. (Also from William Beaty's Web site!)
Neither the earth-ground nor the 1 MOhm resistor are required. You can change the gain (sensitivity) of the detector by changing the value of the resistor, and either shortening or lengthening the antenna.
In contrast to the foil-variety electrometers, this sucker is sensitive enough to detect someone combing their hair at a distance of 5 meters or more (if your antenna is around 1/2 a meter long, and the humidity is low.)
Try building one, and then devising experiments to see and measure how little charge (voltage) the sensor can detect. You'll be surprised, I promise!
Finally, if you're interested in the history, check out the SparkMuseum to see some of the actual original scientific and demonstration equipment from when people were first figuring this stuff out.
If a packet hits a pocket on a socket on a port, and the bus is interrupted as a very last resort, and the address of the memory makes your floppy disk abort, then the socket packet pocket has an error to report.
If your cursor finds a menu item followed by a dash, and the double-clicking icon puts your window in the trash, and your data is corrupted 'cause the index doesn't hash, then your situation's hopeless and your system's gonna crash!
If the label on the cable on the table at your house, says the network is connected to the button on your mouse, but your packets want to tunnel on another protocol, that's repeatedly rejected by the printer down the hall, and your screen is all distorted by the side effects of gauss, so your icons in the window are as wavy as a souse, then you may as well reboot and go out with a bang, 'cause as sure as I'm a poet, the sucker's gonna hang!
When the copy of your floppy's getting sloppy on the disk, And the microcode instructions cause unnecessary risc, Then you have to flash your memory and you'll want to RAM your ROM Quickly turn off the computer and be sure to tell your mom!
This is the Student Web Log for The Westminster Institute for Science Education, which was founded to nationalize broad enrichment to, and reform of, K-12 science, mathematics,and technology education. The WISE mission is to foster open-ended inquiry and exploration and to actively tap creativity and innovative thought requiring critical analysis.
You'll need to install the free Skype software and have a PC or Mac with properly configured microphone and speakers. Note that audio will work even without a webcam.
![[SCHEMATIC OF DEVICE]](http://amasci.com/electrom/e-field2.gif)
![[Drawing: FET and LED soldered to 9v connector]](http://amasci.com/emotor/fetdet1.gif)
