Philip Keller

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Philip Keller

Philip Keller

@pckeller

High school physics teacher with a side order of math

New Jersey, USA Katılım Temmuz 2009
237 Takip Edilen312 Takipçiler
Philip Keller
Philip Keller@pckeller·
@howie_hua Btw, this is the kind of approach taken by math-y baseball fans. If you have hits in 20 out of 30 at bats, then going 5 for 5 will raise your average.
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Philip Keller
Philip Keller@pckeller·
@howie_hua Having covered 20 miles in 30 minutes (which is less than a mile per minute) I would need to travel 5 miles in 5 minutes to get to 25 miles in 35 minutes, which is an increase...
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Howie Hua
Howie Hua@howie_hua·
For today's Mental Math Monday, how would you mentally calculate which is faster? 20 miles in 30 minutes or 25 miles in 35 minutes
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Philip Keller
Philip Keller@pckeller·
@maalmeida85 @PNWPhysics @VernierST Your timing was perfect posting this. Used it yesterday in class -- it's a really nice question. I think we landed on the "expected" solution by analyzing torques around that left support. But you can also use symmetry to get an answer!
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Philip Keller
Philip Keller@pckeller·
@mathillustrated Also, not the main point, but these are not obvious. I can’t define “simplify”. And to clear up the difference between constant and variable, also not easy. “In y = mx+b, x and y are variables and m and b are constants. Now, what happens when we change m?” Wait…you just said…
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Ralph Pantozzi
Ralph Pantozzi@mathillustrated·
Students develop understanding of mathematical definitions through examining formal definitions and working with provisional ones. This is good pedagogy. #iTeachMath
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Philip Keller
Philip Keller@pckeller·
@TheReelRandom Me too today. But also the wordle bot! That does take some of the sting out of it.
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RandomWhiteGuy
RandomWhiteGuy@TheReelRandom·
Wordle 1,214 X/6 ⬛⬛⬛⬛🟨 ⬛⬛⬛🟩🟩 ⬛🟩⬛🟩🟩 ⬛🟩⬛🟩🟩 ⬛🟩⬛🟩🟩 ⬛🟩⬛🟩🟩
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Philip Keller
Philip Keller@pckeller·
@jamestanton Like a sudoku gone south, typos and little math-o’s are easy to make in this algorithm and then kinda hard to find. I would never have noticed it. And to be fair, you got the same answer both times. That’s good enough for me
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James Tanton
James Tanton@jamestanton·
One thing to notice is my typo!
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Philip Keller
Philip Keller@pckeller·
@physicsnico This happens at my school too! It's incredibly nice and not at all like I remember my own high school years. We were much crabbier back then...
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Philip Keller
Philip Keller@pckeller·
@Hookean1 @kilroi22 This is a fun one. For contrast, you can also make a set that has equal spacing to “hear the acceleration”. And if you have sound sensors you can graph to see the spikes, either equally spaced or getting closer.
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Dr Dan Jones
Dr Dan Jones@Hookean1·
Physics teachers. Great idea from Jeff Bigler
Dr Dan Jones tweet media
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Philip Keller
Philip Keller@pckeller·
@jamestanton Now the coin is rolling around the inside of a circle! It has to travel further along the surface bc the surface is bending backwards.
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James Tanton
James Tanton@jamestanton·
Wheel of radius 1 makes one full rotation if rolls distance 2π along a straight segment, or a distance 3π/2 over a 90° kink. What about on the inside of a 90° kink, down one side then up other? Generalize for kinks of a general angle θ.
James Tanton tweet media
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Philip Keller
Philip Keller@pckeller·
@jamestanton This reminds me of the puzzle about the coin rolling around the exterior of a bigger coin. Some of the “rotation” comes from the bending of the surface it’s rolling on.
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James Tanton
James Tanton@jamestanton·
A wheel of radius 1 makes one full rotation if it rolls along a segment 2π long. But what if that segment as a 90° kink? How long should the segment be now? (Assume starts at endpoint with a radius perpendicular to the segment and ends similarly.)
James Tanton tweet media
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Philip Keller
Philip Keller@pckeller·
@pickover It's a decision we have made about notation. If you claim that √9=±3, why would we ever see the expression: ±√9 ? The fact that we do use that second expression means that we don't think that the ± is already baked in to the √ symbol.
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Cliff Pickover
Cliff Pickover@pickover·
This is a math joke, circulating widely on the Web.
Cliff Pickover tweet media
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Ariel Serkin
Ariel Serkin@aserkin·
Anyone else add items they’ve completed to their to do list just so they can cross them off?
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Louie Klein
Louie Klein@LouieKlein_·
Teaching is actually a super easy job now here in the 2020s because we have 49 apps and websites that we get to use on the daily that basically do the job for us…. Right?
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Philip Keller
Philip Keller@pckeller·
@helenrey Math and physics teacher here. I see no reason to require the arrow. And if one were to require the arrow, why only one of them? Unless there is some context that tells us x can’t be negative…
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Philip Keller
Philip Keller@pckeller·
@Tweetlahuac It’s similar to the risk of teaching misconceptions - you can unintentionally end up, well, teaching the misconception. I vote for skipping it entirely.
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Profe
Profe@Tweetlahuac·
im teaching a new (to me) course and there is a learning styles (LS) lesson in the curriculum. what should i do?
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