Recent content by 0pt618

Okay, makes sense. I read and learn physics for fun. It's not a homework problem.

Question edited to be more precise.

No - why do you ask?

Let's ignore gravity in this problem for simplicity. For a wheel rolling without slipping on some surface, the rest point is the point at a given instant of time that is in contact with the surface (the rest point has zero instantaneous velocity). If the wheel is rolling at constant velocity...

The point mass (aka particle) is a fictional but useful concept. However, I have yet been able to find a definition of what exactly a point mass is. It is commonly accepted that a point mass does not have an orientation, and thus only 3 coordinates to determine its position are required (as...

Thanks A.T. - is there a classical counterexample?

For a 2-body system that is not under the influence of an external force, the forces on each body (assumed to be point particles) always point to the center of mass the 2-body system. Does this still hold for general N-body problems, where N>2? Specifically, does the net force on each body...

Thanks JBA. Would you know any resources, such as book chapters or webpages, that sets out the physics of mechanical (man-made) water wave generation?

Thanks Xu Shuang for your reply. It's been a long time ago since I studied special relativity. But from your equation, it seems if the velocities are all much less than the velocity of light, then the statement would be valid, correct?

The only man-made water waves I can think of are artificial waves in specialized swimming pools. If the wavelength of the water wave is W, does the instrument generating these waves have to have dimensions on the same order as W? In other words, if you have a small object, can you generate...

Claim: The acceleration (both direction and magnitude) for any object is the same in any inertial reference frame. Is this claim true? I think it is, but someone mentioned to me that time may be an issue as it's not agreed upon in all inertial reference frames. I'd appreciate any references...

This question arose as I was studying mathematical modeling in fluid mechanics. It was posted to math.stackexchange, but there a was a lack of response, probably due to the applied nature of the problem. One form of the Buckingham Pi Theorem says that for nn variables with kk dimensions, the...

Yes, I see it now. Thanks. In light of this, I think care needs to be taken to select either the generalized First Law or the more restrictive (but usual) First Law. For the example I gave, we can need to apply the generalized First Law: ΔU+Δ(KE)+Δ(PE)=Q−W and include the "pushing" work on the...

Hi Chet, this makes sense. But would you mind letting me know in which section or page the generalized First Law is stated in the Smith & Van Ness book you mentioned? I found the 7th edition in the library, but am having trouble finding it explicitly stated. I did find, on p. 23, Section 2.4, it...

A box is initially at rest on a frictionless surface. David then pushes it and the box moves across the frictionless surface. Let's discuss this process in the context of thermodynamics, especially the First Law. One way to state it is: ΔU=Q−W (where positive W is work done by the system...