31 December 2011
28 December 2011
26 December 2011
21 December 2011
18 December 2011
|How do you arrange for effective group work in class?|
But effectively moderating a problem solving session requires more than just a state trooper-style presence. Especially since he teaches freshmen, Curtis is continually teaching the students how to collaborate effectively. He's showing them skills we take for granted in our own or our seniors' academic lives. For example, he'll say, "You look like you're stuck. You haven't written anything down for ten minutes. Why not ask your neighbor there for help?" Or, "Okay, Joe, you've told John how to do the problem. Now, John, you try it for a few minutes by yourself. Don't ask Joe for help again until you are well and truly stuck." Or even, "All three of you are working together. So you should either all have the same final answer, or you should be arguing vehemently. Which is it gonna be?"
What I did: In my own 11th and 12th grade college-level class, I gave them a fun problem (see the post about the soda bottle raft.) I insisted that everyone work silently for 5 minutes until everyone had written down a reasonable approach. After 5 minutes, collaboration was unlimited amongst the entire class. They were told that I would collect a problem from everyone, but that I would grade only one, chosen randomly. Everyone would earn the same score.
Afterward, I graded the randomly-chosen problem, cut off the student's name, and posted his work on the bulletin board with the grade. Two of my sections earned essentially full credit. One section earned just 1/10, though. And interestingly, that student's work has been simply fabulous over the past week -- I think he took a bit of ribbing from his friends.
14 December 2011
|And if any soda company would give me money, I'd use their|
brand name in the problem statement. :-)
- Mr. Jacobs’ friend Brian Jackson saved two-liter soda bottles throughout his senior year of college. During “Haverfest," he duct taped the bottles together to form a raft. He then successfully floated himself out onto the duck pond.
12 December 2011
|Today's post: making our horses drink.|
07 December 2011
03 December 2011
30 November 2011
|What's the buoyant force on a lionfish? I ain't doing this|
demo, but you can see the demonstrations I do do at this link.
27 November 2011
17 November 2011
15 November 2011
|Woodberry Forest 21, EHS 12 in 2011. But this picture|
is from 2010.
11 November 2011
(1) How do you help your students review for a major cumulative exam?
(2) Why does your email say "Nacho Man?"
The point is, extra credit and food provide significant incentive to bring students into the classroom during what otherwise would be wasted independent study time. Once students are in the classroom working diligently on physics questions, learning is happening even if music, conversation, and nachos are happening simultaneously.
Check out this post.
Peter Chen, a student who is well-versed in video production, intends to create a "cooking show" style clip about Nacho Day in our physics department. I'll post the link in a month or so.
08 November 2011
1. A possible force vs. time curve for a ball struck by a bat is shown in the figure.
(a) Calculate the impulse delivered to the ball.
(b) This 0.25 kg ball was initially moving toward the bat at a speed of 20 m/s. Calculate the exit speed of the ball.
Understandable mistake, combo platter: The student who used the max force rather than the average force to calculate impulse, AND who didn't account for the ball's changing direction, got something like 68 m/s. Well, that's about 150 mph, and still not horrid -- after all, that's only 40% above the typical 100-120 mph exit speeds in the majors. (I'm recalling my Physics of Baseball by Robert Adair; I hope I have that value right. Please correct me in the comments if I'm wrong.) That answer loses only the two points for the direction change issue.
05 November 2011
|Happy and Sad Balls -- which one produces|
more force when dropped onto a force plate?
31 October 2011
26 October 2011
22 October 2011
|Tim and Andy measuring the force applied by a spring|