Recent content by nesp

davep, thanks for the reply. So with something like that view ray system, the targeted area is visualized real time as it's being radiated? And it's done with MRI? I assume the MRI is used to detect movements of the tumor being targeted. How do you know that the linear accelerator is...

Not sure if this belongs here or in the nuclear engineering forum. Many cancer patients in radiation therapy for cancer receive as much as 170-190 rads of daily radiation for 7-9 weeks. When I looked at a radiation chart I found that equates roughly to the dose at 1 mile from a Hiroshima...

Thanks for the link. I'm glad some consider such anecdotal data sufficiently serious to attempt to construct hypotheses, such as oxygen deprivation, which may be suitable for some type of controlled testing.

ryan, at the risk of extending an exchange that went well off track, let me attempt to address your reasonable response in a way consistent with my original intent. The point of my response was not primarily about NDEs, nor did I take a position one way or the other about the subject. For...

Ynaught, in my attempt to simplify for the OP, I oversimplified and equated absolute zero as being the state at which all motion stops in a statistical thermodynamic sense, and all quantum motion stops, including that related to zero point energy. The second is what I was referring to as not...

My point about the 11 Km/s is that it's the slowest possible speed for a meteor collision because it only accounts for the Earth's attraction on a far away object without any other relative motion. When you account for the Earth's orbital speed around 30 Km/s and the meteor's speed you can see...

It would be unlikely to remain in one piece all the way to the ground. At those velocities, atmospheric impact generates tremendous heat and forces on the meteorite, likely exploding it into several chunks and a whole lot of dust. Those chunks would still impact with great force, but the...

It's more than that. If absolute zero were to be possible, it would negate quantum mechanics. So it's more than never having been observed, it also invalidates the foundations of a theory with a plethora of experimental verifications. So I suppose it's OK to say that reaching absolute zero...

In your OP you said by impact time it was 4kg so I assumed that was what remained after going through the atmosphere. If the 4KG is at the point of entry into the atmosphere, this is a more difficult problem. You have to take into account the angle of entry, the mass density, etc...

It might help to think of T as a measurement of the average kinetic energy in the system. Absolute zero would imply no kinetic energy, not even from quantum processes, which is not possible to reach thermodynamically.

What's the formula for kinetic energy? It's a pretty simple substitution if you just want a rough answer for the amount of energy released. Convert to equivalent pounds of TNT if you want an idea of the size of the crater produced. But it also depends on the mass density, doesn't it?

Yes, an inelastic collision is one in which at least part of the kinetic energy is converted into a different form, such as heat. In satellite collisions you don't get perfect elastic or inelastic collisions, you get a mix, with momentum conserved but not kinetic energy. So much of the kinetic...

Thanks for validating some of my reasons for retiring. It's hard to refute lack of logic. Good luck in all of your endeavors. I'm out.

Apology accepted, let's start over. Sorry, I don't know how to use the quote button so if that's the price of entry, I'm out. "So back to your post, anecdotes are meaningless in science. You seem to disagree, so post some evidence to show why we should consider unproven anecdotes." -...

"You made the claim but the few that are valid form the basis for scientific advancement. All right, let's see those scientific studies that verified these valid NDE's. You'll find that you can't just throw nonsense out on this forum and not be asked to prove it." Well, this is...