Talk:Introduction to physics/lecture

Skeleton
Just a skeleton. The section on Newton's laws should be enough for the authors of the kinematics lesson to build upon without having to motivate Newton's laws all over again. The section on the forces of nature is, at this introductory point, meant as a motivational section only. It should also lay out the current state of physics, without getting into mathematical details, so as to entice the student as to what physics has done, and is currently exploring. Ron 13:25, 22 August 2006 (UTC)

Second law
Hm...I have an issue with the Second Law. Wasn't it formulated in terms of the more general F = dp/dt ? --HappyCamper 05:02, 24 August 2006 (UTC)


 * The form given is the actual form used in the Principia, only modified slightly to more modern phrasing. You can read his original formulations yourself at the link provided to the original laws on the article page. What we call momentum today, Newton referred to as "quantity of motion", which he defined as "the product of the body and its motion", which is distilled into what is present on the article page now. It's not very streamlined, I just did this in a few minutes last night because of the horror of the first section. o_O Ron 21:33, 24 August 2006 (UTC)

Intro?
Who on earth wrote this introduction? I suggest banning them right away to eliminate the possibility of polluting wikiversity with any more of their bilge. Sojourner001 18:01, 24 August 2006 (UTC)


 * I was wondering this myself. Their contribution was the impetus that made me write the second section, as I didn't want the page thought a waste. Ron 21:27, 24 August 2006 (UTC)

I did my best to fix it up. --The Winged Self 23:24, 24 August 2006 (UTC)


 * Nice job! I'm going to modify the way mass is defined a little, though, as it's possible for a body to decrease or increase in mass without the number of particles making up the body changing. --Ron 00:06, 25 August 2006 (UTC)

Go right ahead. I didn't really put anything in about relativity and whatnot--The Winged Self 16:03, 25 August 2006 (UTC)

Potential Energy Example
First of all I would not make the question negative, ask which form the potential energy can be transformed to. Second, I would argue that mass is a type of potential energy, although that may be above the level of the reader at this point. --mikeybikey 12:05, 6 September 2006

Scalers?
Shouldn't scalers be under Newtonian Physics? It is kinda hard to find it in the Vector section which may put people off.--Mickyfitz13 19:27, 3 September 2007 (UTC)
 * Added scalars. --Ron 23:40, 25 March 2008 (UTC)

Way over my head
This doesn't seem very friendly toward beginners. Could there at least be a section of things you should already know before reading this? The article links to coordinate systems, and their wikipedia articles. The whole reason I tried wikiversity is because I don't understand the wikipedia articles. Forgive me if I'm missing the whole essence of wikiversity, but I figured it would be a place to go learn something without needing a whole lot of background knowledge. suggestion added 21:09, 25 November 2010 by 98.202.68.204 --Abd 21:48, 25 November 2010 (UTC)
 * It is such a place, but far from every possible resource has been developed. You can help, in fact, by asking even "stupid questions." It is a fast way to get smart!
 * If you look again, start reading again, and as soon as you come to a statement you do not understand, particularly after a little thought, ask, you will be exposing the difficulties in the explanations, and setting up conditions for others to notice and fix them. This will represent you taking some level of responsibility for your own education, instead of expecting others to do it for you, anticipating all those questions. Some aren't good at that, but may be able to answer questions directly, others may be able to help make the explanations clearer.
 * The course, overall, suggests a knowledge of math that may not be completely necessary. A deep knowledge of physics does require at least a conceptual understanding of math, but there is a lot of understanding that doesn't require much.
 * I will start a page to use for those questions, see Introduction to physics/Questions. I suggest starting a section there for any section on the main page that you have a question about, then add your question. You may but need not sign and date the questions using four tildes ( ~ ). I highly recommend registering an account if you are going to regularly participate. This kind of interactive learning can be far deeper and more efficient than simply reading, and each question and answer may benefit others. --Abd 21:48, 25 November 2010 (UTC)

The questions
Ugh. Awful questions, awful explanations of answers. Without looking into exact usage, which isn't explained before asking the questions, the first question asks if displacement is a vector or a scalar. However, the ordinary meaning of displacement is a scalar. I did answer the question "correctly," but only by guessing correctly the intention. If I say that an object moved a foot, I'm not specifying which direction the object moved. It could be any direction. So it's a scalar. But if I say it was displaced to the west by a foot, I've specified the direction. Vector. I hated questions like this in school, where the more the student knows, the less obvious is the answer.... Those questions are testing to the teaching, bad idea. And they were not even that, they were testing to the authors' idea of the teaching.

I appreciate the effort put in, at the same time as I'm criticizing the work product... We will, I assume, improve these resources over time. --Abd 22:20, 25 November 2010 (UTC)