Teaching Electric Circuits? Climb On Board The Coulomb Train! | e=mc2andallthat

I’ve said it before and I’ll say it again: teaching electric circuits is hard.

Providing your students with a conceptual model can, in my opinion, be immensely helpful. In recent years, I have used what I call the Coulomb Train Model (CTM). It is essentially a variation on the “stiff chain”-class analogies that some researchers have argued as being particularly useful in developing students’ understanding.

One reason why I like the CTM is that it provides a physical picture to aid students’ comprehension of many of the electrical equations needed at GCSE.

Of course, any analogy or model…

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Ohm From Ohm | e=mc2andallthat

Amongst the myriad inconveniences and troubles of a Physics teacher’s life, the choice of the symbols commonly used to represent voltage, current and resistance, must surely rank in the top ten.

V is for voltage in volts, V

Well, OK, that’s sensible enough. On a good day, I may even remember to call it “potential difference”. The sage advice of “Never use two words when one will do” is widely accepted. However, as a profession Physics teachers have decided to go it alone and completely ignore it. One can only hope that everyone got the memo.

R is for resistance in ohms, Ω

R for…

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Assessment Will Eat Itself | e=mc2andallthat

Seemingly a lifetime ago I remember writing about the worst mark scheme ever written. Jon Tomsett recently wrote a searing blogpost about a more recent version.

Laura then took me to her classroom, where piles of coursework were strewn across every table, and showed me what she has to mark. She has 29 students’ work to assess, having to write comments to justify her marks in 7 boxes for each student. That is 203 separate comments with minimal, if any, support from OCR. Page after page of assessment descriptors without any exemplar materials to help Laura, and her colleagues across the…

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Teaching Magnification Using the Singapore Bar Model | e=mc2andallthat

He was particularly indignant against the almost universal use of the word idea in the sense of notion or opinion, when it is clear that idea can only signify something of which an image can be formed in the mind. We may have an idea or image of a mountain, a tree, a building; but we cannot surely have an idea or image of an argument or proposition.

— Boswell’s Life of Johnson

The Singapore Bar Model is a neat bit of maths pedagogy that has great potential in Science education. Ben Rogers wrote an excellent post about it here. Contrary to Samuel Johnson’s view, the Bar Model does attempt…

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Teaching Magnification Using the Singapore Bar Model | e=mc2andallthat

He was particularly indignant against the almost universal use of the word idea in the sense of notion or opinion, when it is clear that idea can only signify something of which an image can be formed in the mind. We may have an idea or image of a mountain, a tree, a building; but we cannot surely have an idea or image of an argument or proposition.

— Boswell’s Life of Johnson

The Singapore Bar Model is a neat bit of maths pedagogy that has great potential in Science education. Ben Rogers wrote an excellent post about it here. Contrary to Samuel Johnson’s view, the Bar Model does attempt…

Continue reading at:
http://ift.tt/2tYOYDl

Lottie and Lorentzian Length Contraction | e=mc2andallthat

@_youhadonejob tweeted this textbook picture with the amusing and sardonic comment “Little girl in this textbook is 5 m tall”.

I liked @jim_henderson60’s take on this when he tweeted: “You see. Physics helps us all grow tall.”

But then I started thinking, what if the 5 m measuring stick was in an inertial frame moving past Lottie’s inertial frame at a substantial fraction of light speed? (In my head, I named the girl “Lottie”, although “Alice” would be more in the more usual tradition of SR* pedagogy, I guess.)

The illustration could represent that single instant at which both ends…

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Lottie and Lorentzian Length Contraction | e=mc2andallthat

@_youhadonejob tweeted this textbook picture with the amusing and sardonic comment “Little girl in this textbook is 5 m tall”.

I liked @jim_henderson60’s take on this when he tweeted: “You see. Physics helps us all grow tall.”

But then I started thinking, what if the 5 m measuring stick was in an inertial frame moving past Lottie’s inertial frame at a substantial fraction of light speed? (In my head, I named the girl “Lottie”, although “Alice” would be more in the tradition of SR* pedagogy, I suppose.)

The illustration could represent that single instant at which both ends of the 5 m…

Continue reading at:
http://ift.tt/2oQ7NmF