MotoGP: lean machine, part 2 — the Dani data

I rather like the idea of putting Dani Pedrosa's clip from the last post in front of students and letting things be very open -- open to estimation, as well.  But if one would like to hone the quantification, here are some resources.

What does he ride?  

Honda RC212V

How big is he?

About Dani Pedrosa

How sharp is that turn?

Type "Sachsenring Germany" into Google Earth, and it will take you right there.  Here's a fun puzzle -- which turn on the circuit is he making in this screenshot?  [Spoiler alert]

Note that the shape of the riders' turns is not the shape of the road; they're quite skilled at that whole Principle of Least Action thing.  I love how you can see the blackening of the road from the tire-wear from space.  I approximated the turn with the red circle below; if anything, it's a little small.  The ruler-feature on Google Earth is mighty handy here.  I love how you can see the blackening of the road from the tire-wear from space.

Alternately, the circuit specs are here, and here's a map that could also be used to approximate the curvature.

I'll be doing this for sure when I get back to Physics with 11th & 12th graders!

MotoGP: lean machine!

Nicky Hayden (Owensboro, KY)
leads Jorge Lorenzo in Spain 2011

My husband turned me on to Moto GP this summer.  As a rider myself, I find what these riders do just so viscerally exhilarating, I can hardly bear to watch.  If you have not yet seen a motorcycle race, please know that these guys are dragging their knees on the turns, often with the rear end of the bike (or the whole thing!) sashaying in the limbo between static and kinetic friction.  (Here's Casey Stoner drifting; watch as he comes out of the turn.)  The angles are so insane that anyone (not just physics geeks like me) wonders how in the world they are able to do that.  So naturally, I start looking for the perfect clip to lay on my students, and I give you Dani Pedrosa, under the radar gun.

After about 20s, Pedrosa's speed is displayed.  Student questions will drive the analysis.  Have fun!

I've added this one to the collection of clips for Video Analysis that I started in last spring.  The picture is sharper in the original than above.

Trains, planes, and teaching 1D motion, part 2

(There were never any planes.  I was not inclined. ;)

What would it look like 
to have students analyze 
a traffic citation from a 
speed monitoring system?

1. Distribute photocopies of an actual citation.  (I concealed the identity of the recipient and the officer. Don't forget the plates.  If you've not received a citation yourself, I strongly recommend you solicit your friends & colleagues for, er... data.  Here in Baltimore, you can go online and get two amazingly sharp color photos and a video for your $40.)
2. Pose the question:  Was this ticket fair?
3. Students will start asking questions; have rulers at the ready.  You might want to know the make of the car (I Googled the length) or the width of the crosswalk for scale.  With a local citation, you could come with that information ahead of time.  (The photos have time-stamps on them.)
4. Get tech-y with it.  Coach students on making one of the images semi-transparent and overlay them.  Logger Pro will some scaling for them, though perspective is an issue.  They can also do Video Analysis.  (Examples of each below.)
5. Once they start digging, ask -- Was the car speeding?  How well do you know?  What assumptions or approximations are you making?  Is your approximation of the car's speed likely high or low?  How do speed monitoring systems work?
6. The charge: You have been called upon as an expert to testify in this case.  Write up a report for the court with the highest degree of integrity in how you present your findings.  Be sure to include explain how you reached your conclusions as well as the limitations of your work.
7. Prepare for Spontaneous Happy Physics Dance when somebody approximates a scale to compensate for perspective...

At the end of this activity, students will:

• Have a deeper understanding of speed
• Get practice with scaling and different representations of motion
• Have an appreciation for using technology to solve problems
• Know that the driver of this car was speeding, anyway
• Feel empowered to use Physics to fight the Man  (I mean this seriously.)*

*This is a sentence I write with Mary Oliver fully in mind and heart.