Steve4Physics's latest activity
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SSteve4Physics replied to the thread High School Potato paradox.If still in doubt maybe this will help... Consider a mixture of two materials. The amounts of each are ##A## and ##B##. Total ##T =...
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SSteve4Physics replied to the thread High School Potato paradox.On a point of terminology, the problem+answer is not a true paradox. It is an example of a veridical paradox. That is one which appears...
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SHere it should be specified that it's 99% by mass (not by volume, or by particles, etc.). I think about it geometrically, in terms of...
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SI would be interested the methodology of the experiment. I suspect many of the subjects are not literally failing to understand the...
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SSteve4Physics replied to the thread Looking for lab experiments for a High School Physics class.The coefficient of kinetic friction is generally a bit smaller than the static coefficient. Of course, the laws of physics may vary...
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SSteve4Physics replied to the thread Looking for lab experiments for a High School Physics class.From what you have said, it sounds like the students are working at an introductory level. You might need to improvise a bit but here...
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SSteve4Physics reacted to neilparker62's post in the thread Prove that ## 4\tan^{-1}\left[\dfrac{1}{5}\right]- \tan^{-1}\left[\dfrac{1}{239}\right]= \dfrac{π}{4}## with
Like.
Neat geometric derivation of ##\tan(A+B)=\frac{\tan A + \tan B}{1-\tan A \tan B}## if we divide all terms in ##\frac{ay+bx}{by-ax}## by... -
SSteve4Physics reacted to neilparker62's post in the thread Prove that ## 4\tan^{-1}\left[\dfrac{1}{5}\right]- \tan^{-1}\left[\dfrac{1}{239}\right]= \dfrac{π}{4}## with
Wow.
"All in one" derivation of compound angle formulae - based on the video construction. -
SSteve4Physics reacted to neilparker62's post in the thread Prove that ## 4\tan^{-1}\left[\dfrac{1}{5}\right]- \tan^{-1}\left[\dfrac{1}{239}\right]= \dfrac{π}{4}## with Like.
$$\tan x=\frac{1}{5} \implies \tan2x=\frac{5}{12} \implies \tan4x=\frac{120}{119}$$ $$\tan \left( \tan^{-1} \left( \frac{1}{239}...
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SSteve4Physics replied to the thread Prove that ## 4\tan^{-1}\left[\dfrac{1}{5}\right]- \tan^{-1}\left[\dfrac{1}{239}\right]= \dfrac{π}{4}##.For an essentially geometric proof (no standard trig' identities used) see this 3 minute (appox.) video.
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SSteve4Physics reacted to Greg Bernhardt's post in the thread Praise 2025 PF Member Awards Ceremony with Like.
It's been another incredible year spent on PF! Thanks to all contributing members for making it special! This year we're coming upon 25...
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SJust another approach:
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SSteve4Physics reacted to bob012345's post in the thread High School Three Squares Problem with Like.
Here are some more solutions; In each case, the triangle constructed in green is similar to the triangle highlighted in brown which...
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SSteve4Physics replied to the thread High School Three Squares Problem.The solution below is not mine – I saw it on YouTube, here. This is just my summary. 1. Add 3 squares and consider the triangle...
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SSteve4Physics replied to the thread Rotating difraction grid.With the diffraction grating ('grid') like this: - to which axis of rotation (x, y or z) do you think part a) refers ? - to which axis...
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