Recent content by pjhirv

Yes, you got it. Gongrats!

No, you understood me wrong again. I'm not talking about the physicist. I am talking about the students, great majority of them won't be physicists.

No, that's not the point. The point is that I think of these things now when I got the time. So I don't need to use the time in the classroom. I have a right answer before the class starts.

Here's a good example of two different interpretations. Other ones defines the law with zero net force, and the other one says the object is totally isolated and there's no interactions at all. The article suggest that the latter interpretation is still alive just because Principia was wrongly...

I didn't mean that they actually read the Principia. But maybe someone hundreds years before them did read it, and made own interpretations. Those interpretations has lived their own life, when those have been told for future students on and on untill this day.

I agree that Principia shouldn't be red like gospel. That is very true, but unfortunately lots of people still do it. And sometimes those people are the ones who make physics textbooks, and that way they get to influence millions of people with their own interpretation about the "gospel". What...

Interesting article about Newton's first law: https://liberalarts.vt.edu/news/articles/2023/11/philosopher-uncovers-hidden-truth-about-isaac-newton-s-300-year-.html

I must explain that I'm a teacher myself, so that's why I want to be so extremely sure about the form of the law :smile: Thank you everyone to share your thoughts on this topic. I have some great new ideas reading your answers. Please, if you have anything else to say about Newton's first law...

I found different physics textbook quotes about Newton's first law. And it seems that they are very different. Physics for Scientists and Engineers 6th ed. (College Text) - Serway and Jewett: "5.1 Newton’s First Law Newton’s first law does not say what happens for an object with zero net...

In Principia Newton is giving examples of the movement of planets and comets right after the first law. And those things aren't isolated from their surroundings, because the do feel for example gravitational interaction of other planets or the sun etc. So does this mean Newton is really talking...

Some physics textbook writer told me that Newton's first law applies only on bodies that feel no interactions at all. He said that if a body is on rest or moves in constant velocity, there is no external force acting on it. But I have heard another form of the law that says the net force acting...