Recent content by itchybrain

Yes. My assumption that the gravitational potential energy would (conservatively) transfer to elastic potential energy was correct. I just failed to account for the additional energy going into the system ("work-of-the-hand energy"). That accounts for the difference between the 2mgh and the...

In the case of maximum compression, is the spring constant (for any given spring) different than in the in-between cases? I just don't see how k=mg/h (from force diagram) and k=2mg/h (from energy conservation at maximum compression) can both simultaneously be true.

Thank you. That does make sense. The kinetic energy must be accounted for. Maximum compression must be a theoretical case, right? I.e. the spring will always be in the in-between position for any given mass? If, in the case of maximum compression, m*g*(delta-h)=(1/2)*[k*(delta-h)sq] hold...

Let's say a mass is gently laid on top of a massless spring. The spring compresses. There is a change in the height of the mass. Therefore, there is a change in the gravitational potential energy: a decrease. The compressed spring now has potential energy (it has gained energy). The change...

It seems like this has been asked before in the past, but still no satisfactory answer. For example, see the past thread: How do nodes on a string produce tension if they are stationary? Your write-up on the topic mentions that energy is confined between nodes. Is it fair to say that nodes...

I am sure this has been answered many times. But I've read about 40 posts on standing waves, and I still have a "standing" question. I am having a hard time visualizing how energy can be transmitted at a node of a standing wave. Basically, how can an immobile point be pulling on its...

Thank you for all that valuable information, OmCheeto! So anything below 45 degrees gives limited returns. In addition, at location on higher latitudes, sun elevation may even reach >45 degrees, but the sun will likely not spend much time there before diving down to low-yield elevations.

Thank you, very helpful.

AT: I see that now, and agree. Is the decrease in energy as the rays go through more atmosphere negligible, or a pertinent factor?

Wow, looking forward to this. Foundation is one of my favorite books, and I agree that HBO tends to make quality shows. Any estimate on the release date?

SPOILER ALERT: This question will refer to, and may have spoilers, regarding Arthur C Clarke's Rendezvous with Rama. Read below at your own peril. BTW the book is totally worth reading. In the book, the astronauts basically encounter an immensely large cylinder, rotating along its long axis...

Thank you for the very informative responses. Very helpful! To follow up on russ and davenn's sidepoint: is the light more "dilute" if it covers more area? Davenn's initial picture showed two illuminated areas, one at an equatorial region, one at a northern (tilted region). Also, each area is...

My understanding is that the seasonal variation in temperature, amongst many other things, is a reflection of the Earth's tilt. Simply put, at the equator, sun rays fall "straight down" (100% vertical), and all of their energy hits the surface of the Earth. At different latitudes, these rays...

I need some help understanding how Newton's third law applies to field forces (namely gravitation). The third law in contact forces seems straightforward to me. Billiard ball A, which is moving, hits billiard ball B. The collision exerts a force on Ball B, resulting in its acceleration...