Coming Soon: I handed out tomorrow's quiz tonight (and USIYPT 2012 results)

Folks, I've been at the US Invitational Young Physicists Tournament in Oak Ridge, Tennessee.  It was a well-attended event with the highest level of physics in the tournament's 5-year history.  Attending were:

Rye Country Day School, NY

Woodberry Forest School, VA

The Harker School, CA

Vistamar School, CA

Oak Ridge High School, TN

Shenzhen Middle School, China

Calverton School, MD

The standings after the preliminary rounds put (in order) Woodberry, Harker, Rye, and Vistamar in the semifinals.  Woodberry and Rye advanced; Rye's Andrew Mollerus and Michael Thomas defeated Woodberry's Peter Chen and Damien Chang in a taut, tense final physics fight.  Congratulations to Rye on their first USIYPT championship.

So, um, I lived and breathed physics fights for days, and I'm still adjusting back to the school routine.  My pile of work is testing the compressive strength of paper.  So, you'll get the next real post soon.  Teaser:  I graded a homework that included many common conceptual mistakes, including the "fact" that a battery must always provide constant current.  I wrote a quiz to help bust the misconception, and I actually emailed that quiz to the class folder tonight in advance of the actual quiz tomorrow.  I'll explain why I did that, I'll show you the quiz, and I'll explain whether the gambit did or did not work.

GCJ

Want to referee a physics fight?

Okay, that title is overly dramatic.  Sorry.  But it's kinda technically accurate...

At the United States Invitational Young Physicist Tournament, teams present their solutions to four low-undergraduate research problems.  Then, the presenting team is evaluated and questioned by another team!  This process is called a "physics fight," a methodology developed by the International Young Physicist Tournament and adapted for the American version of the tournament.

The actual event resembles a combination of a thesis defense crossed with a scientific conference presentation crossed with a Lincoln-Douglas debate.  Teams are judged not only on their physics knowledge, but also on their ability to engage in questioning and discussion in a search for the truth of the problem.  

Want to be a juror?  See, I'm the president of this tournament's sponsoring organization.  We are in the process of recruiting jurors to referee these physics fights.  If you're a high school physics teacher or college physics professor, then we want YOU.  Everyone who has ever seen this USIYPT in action has fallen in love with the friendliness among participants, the outstanding physics, the poise of the contestants, and the professional  camaraderie amongst teachers, students, and jurors.  (Several invited jurors have liked it so much they've brought a team the next year.)

This year, the USIYPT will be at Oak Ridge Associated Universities in Oak Ridge, TN on February 3-4 2012.  The kicker is, the organization is supported only by student fees, for now.  We can't pay an honorarium, or even for a hotel room.*  But if you can get to Oak Ridge, we'll get you on the field for our intellectual Super Bowl.

*Not yet, anyway.  Anyone know a company or non profit that wants to grant us a budget for this thing? :-)

Go to usaypt.org for further details about the tournament; email me at greg.jacobs@woodberry.org if you'd like further information or a formal invitation as a juror.  (And I'd be happy to talk about physics fights at length on the phone as well if you'd like.)

GCJ

All I need is a box of donuts...

Picture credit:  Paul Vickers

Hi, folks.  The picture to the right shows me in sector 7G, er, at Oak Ridge National Lab's original graphite reactor.  The facility was taken offline in (I think) 1962, and has not been disturbed since.  All controls, dials, seats, labels, everything is just as it was on the last day the reactor was active.  So I entered the control room, sat in the swivel chair, and attempted to cause a Homer Simpson-style meltdown.  I failed.

I haven't posted in weeks 'cause I've been arranging the US Invitational Young Physicists Tournament.  The Harker School of San Jose, California took first place; Woodberry Forest (my school) came in first in the preliminary rounds, but was upset in the playoffs by Rye Country Day School of New York. 

Now I'm desperately trying to catch up with the pile of work I ignored in order to go to the tournament in Oak Ridge.  I'll get back to posting here in a while.  Until then, try to figure out what each of those dials does.

GCJ

The USIYPT is next weekend (Feb. 4-5)

Next Friday-Saturday, February 4 and 5, I will be helping to run the 2011 US Invitational Young Physicist Tournament.  Six teams from across the nation will converge on Oak Ridge, Tennessee, to discuss four research problems in ritualized debates.

If you're near Oak Ridge, stop by -- these debates are quite entertaining, even to a lay audience.  But even if you're not able to attend, you might consider using some problems or ideas from the tournament.

All participating teams have been investigating three of four possible problems:

Dominos: "Numerous domino tiles are balanced on a table or floor with their long axis vertical with horizontal spaces that can be varied. When the first tile is knocked over a domino wave occurs. Predict and measure the speed of this wave and its dependence on various parameters.

Salt Water Oscillator: "Pour fresh water into tall container. Place a cup with a hole in its bottom surface on top of the fresh water. Prepare a solution of salt water and add some food coloring. Pour this solution into the cup on top of the fresh water and simultaneously push the cup down into the fresh water. Secure the cup so that the level of salt water is approximately the same as the level of fresh water. Observe the on-again and off-again flow of salt water into the fresh water. Predict the frequency of these oscillations from first principles, and compare to experiment. Investigate sizes of holes, salt concentrations, and other liquids."

Magic Motor: "Construct a DC motor without a commutator, using a single battery, a single permanent magnet, and a single loop of wire. Predict the frequency of rotation of this motor from first principles and compare to experiment."

Boiling Water: Some people say it is important to put a lid on the pot when you want to boil water for tea to save energy and time. Investigate this phenomenon.

What I love about these kinds of problems is that one could do a cursory experiment in a couple of lab periods.  However, a deep theoretical understanding, coupled with a thorough experimental investigation, takes much more time and effort.  And, there's enough issues to be investigated that different schools approaching the problems in different ways will have lots to talk about.  That's how real physics works -- competing research groups publishing and sharing their own understanding of interesting problems.

 

I think of my school's team as a graduate research group.  At the beginning of the year, I helped them figure out the correct experimental and theoretical approaches; I had to learn a lot about each problem, and then I had to *teach* what I had learned.

 

What was wonderful about today's final pre-tournament practice was that the students each said, "we don't need you right now."  I know I've done a good job when the research group is ready and eager to work independently.  They still had occasional questions, but the questions were of the style that professional physicists ask of one another -- not "you didn't tell me what to do, can I go to lunch?"  :-)

 

I can go on and on about the USIYPT.  In fact, several readers of this very blog are coming to the tournament next week, with the possible intent of forming their own team for 2012.  If you'd like to hear more about the tournament, take a look at usaypt.org, or give me an email.  After Feb. 6 I will post the tournament results here, and I'll mention NEXT year's problems.  I can't wait to get my juniors started on those.

 

GCJ

Physics Projects?

Greetings... been distracted the past week by some physics fights.  Oak Ridge (TN) High School and the Madeira School came to Woodberry on Saturday to discuss and debate the merits of the research projects we've all been working on this year.  Next year we will all get together at Oak Ridge Associated Universities in the first weekend of February. 

The four projects that will be discussed and debated next February are:

Dominos: "Numerous domino tiles are balanced on a table or floor with their long axis vertical with horizontal spaces that can be varied. When the first tile is knocked over a domino wave occurs. Predict and measure the speed of this wave and its dependence on various parameters."

Salt Water Oscillator: "Pour fresh water into tall container. Place a cup with a hole in its bottom surface on top of the fresh water. Prepare a solution of salt water and add some food coloring. Pour this solution into the cup on top of the fresh water and simultaneously push the cup down into the fresh water. Secure the cup so that the level of salt water is approximately the same as the level of fresh water. Observe the on-again and off-again flow of salt water into the fresh water. Predict the frequency of these oscillations from first principles, and compare to experiment. Investigate sizes of holes, salt concentrations, and other liquids."

Magic Motor: "Construct a DC motor without a commutator, using a single battery, a single permanent magnet, and a single loop of wire. Predict the frequency of rotation of this motor from first principles and compare to experiment."

Boiling Water: "Some people say it is important to put a lid on the pot when you want to boil water for tea to save energy and time. Investigate this phenomenon."

Need something to do after the AP exam?  Do you have a few students who are way ahead of the rest of the class and seem bored?  Give them these projects.  Next year, bring 2-4 of them to Tennessee, and let them show off what they've learned.  Want to add a research component to your class or to your science club?  Use these problems.  Do you have a second-year class who's done too many traditional laboratory exercises?  Replace standard lab work with these problems.

If you'd like more information about these problems or the tournament at Oak Ridge, please give a call -- 540-672-3900, or an email to greg_jacobs@woodberry.org. 

Falling behind...

It's been busy busy at Woodberry. Last week we held the US Invitational Young Physicist Tournament on campus (about which more later). Raffles Institution, from Singapore, defeated Woodberry Forest in the final.

As far as the Woodberry team was concerned, the best part of the tournament was the final evening's party at the Holiday Inn Express. Although all the teams socialized, the Woodberry guys* seemed to slather their attention heavily on the team from Brisbane Girls Grammar School. (They're GIRLS! And they have Australian accents!)

We all had great fun for the weekend. The cost of that fun, from my perspective, was a week of falling behind in my classes as I took care of details as tournament director. I have next to me this morning a stack of papers 7.5 cm high... and that's AFTER I spent two nights this week grading papers on dorm duty.
What do you do when you're so hopelessly behind that you will certainly not catch up before next week's end of the term?

Start by recognizing that you're NOT going to catch up with every assignment. In a marathon grading session, it's not worth starting at the beginning of the stack and intending to get to the end. Accept that your work will be incomplete. I picked out a few homework problems at random to grade. It's late enough in the school year that grading papers is unlikely to uncover anything new about a particular student. The diligent ones will still be diligent, the lazy ones still lazy, and the smart ones still smart. The whole purpose in grading now lies in checking up, sending the message that "I'm still watching you!" Just a few spot checks can do wonders for making sure the class keeps up with their work.

The other aspect to catching up with grading is to add as little as possible to the stack. My class starts each day with a short quiz. On Friday, I wrote a 5-question multiple choice quiz about one of the problems from the night before. Don't expect that I'll be grading that problem, now -- this quiz has evaluated their homework, and saved me considerable time.

* Woodberry is an all-boys boarding school, so in this case "guys" is not a gender-neutral term.

Here's one of the three homework problems that were assigned for Friday, which I think I got from the 1997-vintage Zitziewitz-Merrill text, but I'm not sure:

A fisherman’s scale stretches 3.9 cm when a 2.7 kg fish hangs from it.
(a) What is the spring constant of the scale?
(b) What will be the amplitude and frequency of vibration if the fish is pulled down 2.5 cm more and released so that it vibrates up and down?

And, below, take a look at the multiple choice quiz. Notice I've changed values so calculators are not necessary. (Why do the questions start at #15? Because multiple choice quizzes for the whole term go on the same scantron. That means I only have to grade multiple choice quizzes every 50 questions or so!)


A fisherman’s scale stretches 4.0 cm when a 2.0 kg fish hangs from it. The spring is pulled down 2.5 cm more and released so that it vibrates up and down.

15. What is the spring constant of the scale?
(A) 0.05 N/m
(B) 0.5 N/m
(C) 5 N/m
(D) 50 N/m
(E) 500 N/m

16. What is the amplitude of the harmonic motion?
(A) 4.0 cm
(B) 5.0 cm
(C) 6.5 cm
(D) 2.0 cm
(E) 2.5 cm

17. The period of the harmonic motion is 0.40 s. What is the frequency of the harmonic motion?
(A) 0.40 Hz
(B) 2.5 Hz
(C) 4.0 Hz
(D) 0.25 Hz
(E) 5.0 Hz

18. In a new experiment, the spring is pulled down 5.0 cm instead of 2.5 cm to begin the harmonic motion. How does the new period compare with the period in problem 3?
(A) It doubles.
(B) It remains the same.
(C) It is cut in half.
(D) It is multiplied by √2.
(E) It is divided by √2.

19. In a new experiment, a 4 kg fish is attached to the same spring and pulled down 2.5 cm to begin harmonic motion. How does the new period compare with the period in problem 3?
(A) It doubles.
(B) It remains the same.
(C) It is cut in half.
(D) It is multiplied by √2.
(E) It is divided by √2 .