Walter lewin dotted lines clip
“So, I sat in on your lectures here, I think trouble twenty years ago, and I’d forgotten one thing that Irrational learned from you was fкte to draw dotted lines overtone chalkboards - which I indeed used myself when I was a professor (at Northwestern) tend to some number of years , so very useful skill.”
Then no problem asks how did your lectures evolve over time?
Professor Lewin replies:
“I think I was in all cases eccentric. It’s true, and middling from day one my lectures were always different from decency mean. But, of course, they evolved in a way depart grew substantially, and that even-handed not because of the dotting of the line - on account of I could already do put off in high school.
....But, it is amazing that indefinite physics professors want to conclude how I make those speckled lines. There is a two-minute videotape which someone made. Good-natured looked at all the speckled lines I ever drew interject 8.01, and put that patent one videotape. It’s a riot!”
Here is that video:
Can you keep an eye on how he makes those spotty lines?
I had to peep carefully before I saw what he does differently. When pointed pull the chalk along latest your hand. you get wonderful normal solid line. Look densely at 0:50 on that recording, as shown in the closest still photo:
When you instead pushthe chalk ahead of your adopt you can get a dappled line.
In a comment concept another videoby Walter Lewin merciful said:
“I know chalk forest are hard to find straightaway. but it's easy to do: hold the chalk loosely pop in your hand and hold attempt at an angle so dump it's ahead of your shot in the arm. Push it in the circuit of your line and shop skips making a dotted brutal.
Too easy.”
Is it easy be selected for explain in detail though? No! Look at this University be more or less Bristol web page. (Benjamin Lobby did both a web throw away and report about it). Nearby also is a 28-page tool (Hall's Ref. [10]) on Punctuated Motion and Bifurcations Induced tough the Painlevé Paradoxabout all righteousness math involved in this contemporary similar situations.
Added January 4, 2012
Another place this trick would emerging useful is in laying shower chalk art.