Genady

The entire plane or some parts?

This article suggests that COVID-19 cases of hospitalizations and deaths are exaggerated now and most of the reported cases are with rather than from COVID-19. Consequently they recommend reconsidering public measures and related policies. I'd like to hear educated opinions of the members about this. COVID-19 Is No Longer a Public Health Emergency | Time

Here is a suggestion to produce perpetual motion using buoyancy. Consider this kind of device submerged in water: It has two wheels with a belt, and cups attached to the belt. I drew two cups on each side, but the belt can be as long as needed and there can be as many cups attached as needed. Each cup is covered with a flexible membrane with weight attached to the center of the membrane. When cup is on the right, the opening faces upward and the weight pushes the membrane inward. When cup is on the left, the opening faces downward and the weight pulls the membrane outward. Thus, the cups on the right have smaller volume than the cups on the left. Consequently, the buoyancy force on the left is greater than on the right, and the device starts rotating clockwise. Each time a cup crosses from left to right over the wheel on top, its membrane moves inward and its volume decreases, but at the same time another cup crosses from right to left under the wheel on bottom, its membrane moves outward and its volume increases. So, the motion continues. We know that something is wrong here, but what?

Yes to everything BTW, you did much better than ChatGPT. When I've asked ChatGPT the same question, its response was this:

Here is what Chomsky has to say about ChatGPT and education, especially academic: Chomsky on ChatGPT, Education, Russia and the unvaccinated - YouTube

To see if you have understood it right, think about the following question. Take a pencil 20 cm long and 0.5 cm thick. Compare the buoyancy in these two cases: 1) you push it under water while holding it vertically, 2) you push it under water while holding it horizontally. In the case 1, the pressure difference between the water underneath and above the pencil is greater than in the case 2. Is the buoyant force different in these two cases?

To be specific, let's say you are in the plane. You clock the time it takes for photon to get from the source to the seat, 0.5 m, and calculate the speed of light, c. I am on the ground. I clock the time it takes for the same photon to get from the same source to the same seat, 200+ miles, and calculate speed of light, c.

Nope. Only one photon left the light source and it did not bounce - there are no mirrors in this experiment. It just left the source and travelled to the seat. Let's to be specific, have a photosensor on the seat that received and registered one photon.

Sometimes exaggeration helps. So, in addition to wonderful explanations and examples above by Eise and others, consider this. Instead of a train, let's do it in a plane, a very fast one. The light source is installed in the plane directly above seat 17A facing straight down to the seat. The plane is flying. When it is above NYC, the flash of light goes out. After very short time it hits the seat 17A. But the plane is really fast. By the time the light hits the seat, the plane is above Boston. The seat 17A moved 200 miles, from NYC to Boston. However, the light hits it anyway. Thus, the light went 0.5 m down and 200 miles NE.

My first language was Russian, too. I don't practice it many years now, but perhaps could help you if you have problems expressing your thoughts or interpreting some responses.

I'd recommend, reading. A lot of reading.

I've interpreted this dance as a "war dance" rather than a mating dance:

I am sorry, but I don't understand the above description. It still looks to me that you are mixing different reference frames. Could you explain it referring to one frame at a time? There are two frames of interest in this situation that I see: Frame A is the one where the clock/mirror is not moving, and the light goes vertically. This is what an observer which is attached to the mirror observes. Frame B is the one where the clock/mirror is moving to the right, and the light goes diagonally. This is what an observer moving to the left relative to the mirror observes. What is your objection?

I am not sure about this. Let's see if they ask a clarifying question.

I disagree. A free falling body is at rest = not moving in its own reference frame.

Yes, it says, unavailable. But I can see other PBS videos. Also, sometimes I get a message saying something like, unavailable in your area, but this just says, "This video is not available." Well, I don't think you can do anything about it

Oops?

On the reefs of Bonaire.

Here they do:

What about unknown knowns? Why are they not on that list?

This was a mistaken conclusion in the OP. Per the data given, v=0.655c.

The clock moves .866 m in the time the light moves 1.323 m. Thus the clock speed is v=.866/1.323=.655c. The time dilation for this speed, gamma=1.323. The time of the full trip of light is (1 m)/c in the clock's reference frame, and (1.323 m)/c in the external observer reference frame. I don't see any conundrum. This is what time dilation is.

This is incorrect. In the time the clock moved .866 m the light covered not 1 m but sqrt(1+.8662)=1.323 m, i.e., 1 m vertically and .866 m horizontally.

How do you get v=.866c? Is it a given?

For me, it would be very sad. Plus, some of the goals are such that failure to achieve them might be quite painful. E.g., one of my early goals was escape from the USSR. A failure in this one meant more than just not escaping. It meant trading my warm city of Baku for much colder places.