Ways of refreshing physics knowledge?

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Ways of refreshing physics knowledge?

OmegaKV
As a prerequisite for another book I am reading I thought it would be a good idea to refresh my memory on electromagnetics. So I opened the Griffiths Electrodynamics textbook and started doing a random problem (2.45 in the picture attached). But after spending a few hours on it I got frustrated and gave up. I looked at the answer key and it turns out the answer uses a non-intuitive "trick" from a problem 40 problems earlier.

This is bullshit. I thought the problems would be a fast-track to refreshing my physician knowledge, but they turned out to be a big waste of time. I would have been better off just reading the text. I am pissed off that the author wasted my time like this. All the problems in the Griffiths book are similarly difficult. They just test your ability to do complicated math using non-intuitive tricks rather than testing your knowledge of physics. Totally pointless waste of time.

Anyway, does anyone know of any good resources for learning/refreshing physics knowledge? Like, a set of problems to solve, so that you don't have to reread a whole textbook? Except it should be a sane set of problems unlike the ones in the Griffiths book. I am looking to refresh my knowledge of all areas of physics (mechanics, electromagnetics, and nuclear physics).

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Re: Ways of refreshing physics knowledge?

OmegaKV
Now that I think of it, solving physics problems is really a form of idolatry, because you are just doing complicated crap that was devised in some professor's mind.

Maybe it would be better to study something real, such as planetary orbits if you want to learn mechanics. Look at the motion of the planets, and see if you can model them with the laws of mechanics. Electricity is harder because most of the electricity we deal with is man-made.
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Re: Ways of refreshing physics knowledge?

Allen
That would assume that planetary orbits are real.
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Re: Ways of refreshing physics knowledge?

OmegaKV
Can't you confirm they are real using a telescope?
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Re: Ways of refreshing physics knowledge?

Allen
I wouldn't have thought so.
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Re: Ways of refreshing physics knowledge?

R.C. Christian
Flat earth is a theory for idiots who are too stubborn/suspicious to fall for the mainstream agenda (mainstream A), because they like to think they're smarter. It's mainstream B.
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Re: Ways of refreshing physics knowledge?

Allen
Perhaps you could summarize why you believe in the globe model. It would be a good test of whether you are capable of writing multi-sentence posts expressing somewhat complicated ideas.
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Re: Ways of refreshing physics knowledge?

fschmidt
Administrator
Occam's razor applies here.  Newton's simple laws of motion and gravity explain all motion we see both on Earth and in the sky.
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Re: Ways of refreshing physics knowledge?

Allen
How does Occam's Razor apply here and why would you want to take magical religious concepts such as gravity into account?
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Re: Ways of refreshing physics knowledge?

OmegaKV
In reply to this post by fschmidt
Maybe Allen has a better theory that is simpler than the mainstream one when taking more factors into account (e.g. the lack of parallax effect). I am curious to hear Allen's explanation for the apparent motion of the planets.
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Re: Ways of refreshing physics knowledge?

Allen
We probably can't know what actually happens with lights in the sky at this stage, put presumably there are infinite mathematical models that would map the movement of celestial items.
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Re: Ways of refreshing physics knowledge?

R.C. Christian
In reply to this post by Allen
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Re: Ways of refreshing physics knowledge?

Allen
If you are trying to talk about ships going over the earth's curvature, you can debunk that with a pair of binoculars, or better yet with a camera with a zoom lens. It was fairly obvious from your previous posts that you are stupid and know nothing about this or any other subject, but thanks for confirming.
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Re: Ways of refreshing physics knowledge?

fschmidt
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In reply to this post by Allen
This is true of most scientific questions, and Occam's razor says to just pick the simplest model.  I would add to Occam's razor that one should prefer models that aren't just mathematical but also are conceptual.
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Re: Ways of refreshing physics knowledge?

Allen
That is not a correct understanding of Occam's Razor, but OK then, the simplest model of the sun is some guy dragging a chariot with burning material around the sky and this also explains historical accounts of the sun stopping, going slower or faster etc., so lets believe that. Obviously the mainstream understanding of the solar system can be immediately dismissed as it takes years of formal education coupled with a suspension of disbelief and tolerance of various contradictions to be one of the few people who have some nascent understanding of it.