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I've been staying quite busy here in Charlottesville, and if you want a sneak peek at what I've been up to lately you can visit this amazing math site (it should be finished by the end of December - this was my the "big news" I mentioned in the last update, but as is often the case, things always take a bit longer than expected).

I updated the mirrors page a bit, and added a longitudinal wave simulation which I have shown at several talks I have given, but never quite found enough free time to put it up on the web. Sorry about that.

My latest article on DOUG is all about physics (in terms of Lingo), and actually made it in to the November Top Ten!

For my next update, all this news will become a mere "older news" link, since the next update will probably be in the Year 2000. Happy Holidays and Happy New Year to all of you that have visited this site, and those have dropped me a line during the past four years while this site has been growing! Enjoy!


The summer has zipped by, and I have now taken a new job in Charlottesville, Virginia. My site will be moving from Santa Fe, NM to a new location later this week, so it may be down for several days. I suggest you use a relatively recent mirror. If you want to drop me an email message, please use for the next week.

The site was recently reviewed at ( that good? :)

The mirror at UNH has been removed. I'll fix that link on my mirrors page when the site goes back up after the move. If the plans change at the last second I'll let you know.

My DOUG article is located here. After getting 'published' on DOUG..can I possibly do better than that??

Stay tuned for some BIG news in the next month...


First, let me say I'm sorry to those that have written me and have not yet heard back, but let me just say I've been exceptionally busy this past few months (I realize that is no excuse, and when my students use that one I'm usually not smiling!). If you did send me an email message, and you are patiently waiting for a reply, please go ahead and drop me another line...I'll try to get back a bit more quickly :)

As I mentioned in the previous news (four long months ago), I was teaching a rather heavy load last semester. My Department Chair (Dr. Richard Morrisson) unexpectedly passed away. Those that knew him (he was an undergraduate at Princeton and got his Ph.D. at Yale) will remember him with kind thoughts. He was a fascinating individual who recently sparked a lively debate (in The Physics Teacher) about the varying definitions of weight and weightlessness in current physics textbooks. I volunteered to take over some of his classes in the middle of the semester, and have now accepted the position of Department Coordinator (all the basic duties such as staffing, course scheduling, and programmatic development and revision, etc.). This is a very small department (right now it consists of me and several adjunct faculty), and I'm currently in the process of hiring a new faculty member. I have been busy...

For those that are interested in how I develop some of these nifty things with Macromedia Director you can stop by Director Online for an article of mine that is tentatively scheduled to be 'published' on July 21st. I'll let you know about the direct URL when it goes up.

This site was recently selected at one of the Top 100 Educational Sites, and as a New Scientist Magazine Hot Spot.

As a student I got used to teachers having a difficult time with my name, and as a teacher I can't tell you how many times students spell my name incorrectly when turning in lab reports, but one would think Macromedia could get a bit closer than Ron Phaff...check out this link. I hope they fix that one of these days, but since they make Director (which is an amazing tool) I guess I won't argue with them. At least I now know why some emails roll in with that particular spelling.

The MacWorld Expo in NYC runs July 21-23. I'll be popping down on the train just to see if there are any new and nifty things that I need :) If your going to be around, drop me a line and we could grab lunch in the big apple.

For those going to the Summer AAPT Meeting in San Antonio, TX I'll be giving two talks, so drop by and say hi. The meeting runs Aug 3 - 7 (yeah, Texas in August sounds HOT).

Let me say thanks to all the students at Monterrey Tech in Mexico City for all the nice feedback you have been sending to me. I'm glad to know that you find some of the simulations useful for your work in the classroom.

For those that have visited my 'Mirrors' page recently, I know that many of them are no longer functioning, but there are a few new ones popping up. One is in the process of getting set up in Denmark (I'll let you know when it is up), and one was recently set up in Taiwan. I'll try to get the mirrors page updated in the next week.


This site is currently listed as the "Tip of the Month" on the Styrian Physics Server for Schools in Austria! They have many other interesting links, so check it out if you get a chance.

I am still swamped with work, but will be heading down to the APS Centennial Meeting in Atlanta, GA during March 20-26. I'll be giving a short talk on Thursday morning, so feel free to stop by and chat.

I've added a "6-Sided" Snowflake Designer. I never learned how to fold the paper properly to achieve the necessary symmetry, but luckily others let me know about it. Thanks :)

Sorry about the recent server problems. There have been odd problems with the internet connections which "roll" through the hills of New Mexico.


If you have recently sent me an e-mail and I haven't gotten back to you I'm sorry..but I will try to reply in the near future. Teaching five classes (having never taught any of them in the past) is an entertaining and time consuming challenge.

This site was recently reviewed in the Education & Training Journal (Vol. 40, Issues 4 and 5) and was called a "must visit" site. The journal is published by MCB University Press in England.

I also found out that this site was a "pick of the week" on the Kim Komando Radio Show (one of the most popular internet radio shows).


Added a link to the new Introduction to Ultrasound module, along with a new downloadable version of this site. I'll add a few notes here later in the week when I find a few spare minutes (I'm teaching five three credit classes this semester, so time is scarce).


I'll be heading out to the AAPT Winter Meeting in Anaheim, CA for next week. If you happen to be there, keep an eye out for me. I'll be at a "Cracker Barrel" Session Wednesday afternoon from 3 to 5 pm


This site was chosen as a Site of the Week by Entertainment Weekly magazine - both in printed form (Dec 4, 1998) and on-line. Here is a direct link to the review and the site is below.


Where does time go? I've been here in CT for a bit more than two months and getting familiar with a new location has certainly kept me busy (if there are any Director users in the New Haven area, feel free to drop me a line and we could do lunch). I still haven't found an internet provider that has a stable connection or reasonable transfer rate. I'm rather disappointed.

If you want to see a bit of the work I did over the summer you could take a peek right here, but the page will be moving in the near future so don't expect it to stay in the same location forever (and with the web, forever is a very nebulous thing). I'm currently working on a few other projects (have to pay a few bills every now and then) that are geared towards the high school level - stay tuned for more information.

I'll be at the Regional AAPT Meeting on Nov. 6-8 at Yale, so if you'll be there, look for me.

I added a few new items to the site, including some improved instructions on the download page, the answer to some common questions, and two new modules (Center of Mass and Monkey Shooter). On the download page I added another Density Lab Handout that was sent to me, along with a handout that lets people "Explore Newton's Law on the Internet."

This site was selected as a "WebToday Destination" on Sept 29th.


I've moved out to Connecticut to start my faculty position at the University of New Haven, and am still working on getting settled in, so I currently have limited internet access. Thus, if you send me a message, it may take awhile for me to get back to you. And now, on to some actual news...

As a kid I used to love reading through Popular Science magazine, and in this month's issue this site was included among their "Best 50 Sites of 1998." When I looked at the rest of the sites they had listed, it made me feel pretty good to be included among them! If you want a good listing for some educational sites, be sure to check out the issue (or their web site).

I think there may be a few mistakes on the ReadMe that is included with the download of this site, and I'll try to correct any errors as soon as I get my computer set up in my new office.


This has been one busy summer for me, and the site has had a few visitors as well. One thing that I've been working on was updating parts of the IPPEX site. I finished a new version of the "Learn About Matter" module. Feel free to visit it on the web at this location. I'm also working on the "Intro to E & M" material and hope to have that completed in the next few weeks.

The site has gotten a few nifty awards in the past few months, however, sometimes no one lets you know about them - so I find out when people drop me a line, or when I'm web browsing and discover it myself!

On March 19th this site was a USA Today Hot Site, in June the site was listed in a ZDNet article entitled "Search for Intelligent Sites on the Web," and that same month this site was listed in Popular Science magazine in their Web Watch section. This coming weekend (I believe) the site will be in the part of the Sunday Comics in ~ 150 newspapers across the country!

On a personal note, I'm starting to pack up everything I own so I can move out to Connecticut in two weeks, so there may not be many updates for awhile as I get settled in to a new job, new town, etc. Wish me luck - I hope my good old 11 year old car gets me from here to there :)


I have the new version of this site available on the download page. I fixed (hopefully) the serious problem in the floating log simulator.


Every year or so I feel the need to update the overall look of this site, so feel free to drop me a comment or two about this new look. If I find time I'll update the look on all the older simulations, but for now, just future experiments will have the "new" look. However, I have a feeling I'll run through and update many things this summer since there are a few changes I would like to make to several modules.

I've added two new modules - a histogram builder, and a phased array (relatively early version, fast computer a good idea).

This site had over 20,000 visitors last month!


It was a busy month. A new mirror of my site was set up (thanks Taha). You can find the link on the mirrors page. A visitor to my site pointed out several bugs to me. One major one was (and still is) on the floating log module. I'll be working on that one during May - it is rather old so needs a bit of rewriting to get it up to modern standards :) The density module also had a few smaller problems related to changing the density of the liquid in the pail. I posted a new version of that today and hopefully all the problems have been fixed.

As for the stand-alone PC version, there are still some problems I'm trying to correct.

In the next week I'll have a new "histogram" module posted, so stay tuned!

I got this message earlier in the month: "Your site--Explore Science--has been chosen as a selection for the Scout Report (April 3, 1998), the premier weekly collection of useful Internet sites for discerning Internauts. Care is taken in the selection of items included in the Scout Report. Basic criteria include depth of content, author, information maintenance, and presentation. The content of each resource is briefly described."


I now have an "older news" section at the bottom of this page.

This site was recognized by the following groups during the weekend!


Happy birthday to my sister! This site was Blueberry's Chilled Site of the Day on Saturday. Without a doubt one of the strangest looking blueberries I have ever seen :) It was also given a "Top Ten" ranking from a Kids Review. The Yahoo review (which seems very "Twilight Zone-like" is listed on the History page.

I added a module that lets your students see if they can correctly determine the minimum, maximum, and current temperatures from a min/max thermometer. I posted several updates in the past week on the download page (thanks to those that let me know of the problems). More ideas keep popping into my head for new stuff, but finding spare time is always a challenge. Just remember, if you ever have any ideas, pass them along, and if any multimedia developers out there ever want to contribute to this site, please drop me a line. Also, if you have created a publicly accessible mirror of this site, please let me know.

I am still working on the stand-alone windows version (it's in my pile of things I want to get done soon).


The server problems have continued a bit, but problems seem to be mostly under control. The HD on our server died during the 3/1-3/9 week and it took us a bit of time to realize it was going. With the new HD a lot of the software was upgraded, so there are still a few crashes occurring. I made a small change to the orbit simulator that should take care of one main problem (that one will be rewritten this spring/summer).

On a personal note, I was recently hired by the University of New Haven, and will join their Physics Department this coming fall. I'll also be at the Joint APS/AAPT meeting next month in Columbus, OH if you want to chat about any of this fun stuff.

I noticed that this site was a Yahoo Pick of the Week earlier in March and will post their icon on my site in the next few weeks when I find some time, along with the rather entertaining review they had posted on their site.


I apologize for the server problems this past week. Bookmarking my mirror sites (see updated list) might be a good idea - but hopefully that problem is over with for at least a bit. I added a new module under optics which lets you see if the quickest way to get from Point A to Point B is really a straight line. I made several small changes to a few things, so please download the update if you want the latest "stuff."


The site has won several other awards. Please check out the history page if you are curious (gifs are there with the links to the award sites). My UM mirror site is still under construction due to the fact that I haven't been able to get more HD space here at our fine National Championship institution...actually, I'm still trying to get a computer at my desk...working on my site with my 28.8 modem is getting more and more time consuming (ok...I'll stop complaining now).

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