Recent content by Alan McIntire

Thanks for that reference. It's just what I was looking for. I realize that clocks on a rotating disc cannot be synchronized, but the force at a point on the rim should have a unique answer. Either the force of a given weight tied to a string with a given tensile strength on the rotating rim...

I first thought of this problem when I came across the "Ehrenfest Paradox", and realized that as velocity approaches c, the measured force must diverge to infinity as the velocity approaches c.

*********************************************************************** Special Relativity does account for twin paradox. I get the following from a book by Paul Davies. Assume Alpha Centari is exactly 4 light years away, and one twin is traveling there at 4/5 speed of light. (Using a 3,4,5...

I get the following from a book by Paul Davies. Assume Alpha Centari is exactly 4 light years away, and one twin is traveling there at 4/5 speed of light. (Using a 3,4,5 triangle I avoid complicated messy fraction in my computations. Traveling at 4/5 the speed of light, from the point of...

Convert units to where c =1 (light year/year) Acceleration in units of ( 1 light year per year per year which works out to about 0.97 Earth g) distance in light year units. Then with acceleration g light years per year per year distance in light years Speed of rocket as a fraction of c=1...

If you're on a coast, watch distant vessels, and note that the masts of the vessels don't disappear below the horizon until after the rest of the ship has gone below the horizon. If you DON'T live near a coast, wait until the sun is setting on the horizon, about one solar width above the...

Thank you for the link. When I was watching the Pterodactyl attack, I thought it was unbelievable that any living creature could pick up a grown human. The Texas Pterosaurs were supposed to have a mass of 100 up to 200 Kg. Nowadays, the most massive flying bird is the Kori Bustard...

I recently watched a rerun of "Jurassic World" on TV. Seeing the pterodactyl attack, I got to thinking; Is there a formula to determine the maximum weight a flying bird, bat, pterodactyl, or whatever can have given the force of gravity g at the planet's surface, and the atmospheric pressure?

Figure Flash is "racewalking". From Flash's point of view, letting H= heel of foot, C=center of foot, T= front of foot, from Flash's point of view, he hits H..C..T all within a foot of each other. From the manhole point of view, rather than the ground being contracted in length, it's...

In reply to Peter Donis: c^2/a = (meters/sec)^2/(meters/sec^2) = meters which is the maximum length something can be, even Superman, before it automatically falls apart under gravitational acceleration, like the two spaceships (head and feet) and the connecting rope (body).

After thinking about it, I see I was wrong about the black hole- I suppose a Neutron Star would do it, as in Larry Niven's science fiction story "Neutron Star", where a character orbited too close to a Neutron Star and was pulled apart by tidal stresses. Reread that link I gave you, remember...

Peter Donis, you're wrong on c^2/a. See .http://skfiz.wdfiles.com/local--files/archiwum-2005-06/Spotkanie%20SKFiz%2024III2006%20-%20Bartlomiej%20Szczygiel.pdf There IS an upper limit on how much a body can accelerate without coming apart; For example, let's try 1 light year per year, then...

Thanks for that link, Mister T. Peety, it's SIMILAR to to pole/barn paradox, but unlike the pole/barn paradox, Grinkle's hockeystick/Antman is constantly touching the ground. With discrepancies in x', x, t' and t, the only resolution for the hockey stick is plenty of wear and tear on the...

I think I'm right and Dale, pervect, and Rindler are all wrong. c = 299,792,548 meters per second. 0.999c =299,792,755.45 meters per second. From the hole's perspectrve, since 1 yard = 0.9144 meters, Flash will be over the hole for .9144/299,792755.45 = 3.05 /10^9 seconds. The distance...

The superhero "Flash" races over a 3' diameter open manhole at 0.999 the speed of light. I realize that this exceeds escape velocity on earth, so assume the running is being done on Terry Pratchett's "Discworld" https://en.wikipedia.org/wiki/Discworld From Flash's point of view, the manhole...