swansont

You don't know how to calculate the force due to the acceleration of gravity? F = ma m is given. What's a?

But Xenon is inert. How does it react? I was under the (quite possibly mistaken) impression that the euphoria was simply due to the displacement of oxygen, much like asphyxiation/hypoxic euphoria.

What do you know to be true of the net force at terminal velocity? And what are the individual forces acting on the object under that circumstance?

No need to feel embarrassed. Spotting mistakes is often a function of having seen or made them, i.e. much more a function of experience than intelligence. And you shouldn't feel a need to apologize (IMO) for not having a great deal of experience.

This particular thread was supposed to be about alleged censorship, and not about any speculative science. After the original thread was closed, it appears the discussion was continued here. However, that defeats the purpose of closing a thread. So, I'm closing this thread, too.

90º in the calculation, but note that the formula uses [math]2\theta[/math], so the elevation angle is 45º, which is exactly what you'd expect for maximum range.

This one? They don't accelerate for the same length of time, or their acceleration is not a constant (i.e. it's a function of time) (If you are referring to questions in post #18, I'm not going to address them as they are off-topic.)

The planck length is the scale at which you need a theory of quantum gravity. I don't see a reason (though I'm not looking very hard) why a limit on a photon's wavelength would necessarily be tied to that.

You don't have to detect it mid-flight to know which path it took. You can use entangled photons and circularly polarize the light in opposite helicities for each slit. Measuring the polarization of the photon that went through the slits as well as the entangled partner tells you which slit it went through, and this destroys the interference pattern. http://grad.physics.sunysb.edu/~amarch/ The general class of experiment is called a "quantum eraser" experiment, in case you want to search for more examples.

Two different accelerations that leave you with the same final speed. The question is what is your interpretation of the statement? You seem to be envisioning a different scenario than is laid out by the OP.

I don't agree. That scenario does not reflect the one described in the OP, where you can accelerate an object for up to 10 seconds, and both achieve the same final speed. That doesn't matter. An object having 100 J of KE for 10 sec and another having 100 J of KE for 15 seconds still both have 100 J of KE.

Coherence is a little more subtle than this. You can make sunlight interfere, even though it's not a coherent source like a laser. The issue is, how coherent is it — it's not a binary condition. Coherence is two waves having a definite phase relation, and this can be maintained for some length of time, which means it will be maintained over some length of travel. Laser light can be coherent over kilometers of travel, but as long as the light is coherent over the length of travel where you have a path difference in your interferometer, you will get interference. There's an excellent primer on coherence here: http://skullsinthestars.com/2008/09/03/optics-basics-coherence/

It better be. They sell it bound with chlorine at the grocery store. Seriously, though, you can buy alkalis online, so I imagine you can sell them, too.

I was referring specifically to saltwater intrusion as a local phenomenon. Depleting an aquifer in New Jersey in the US is not going to cause intrusion in a coastal area of Africa, AFAIK. As others have pointed out, water is not being destroyed; it gets cycled back into the ecosystem. One issue is that there are more people, which causes problems, and if you overburden the system it can cause problems. Adding parking lots and roads causes more runoff and less absorption, which affects aquifer replenishment. However, I think you are underestimating how much the oceans serve as a source for evaporation, and aren't appreciating how much water that represents. Bottled water represents a tiny fraction of the overall, and it was water we were going to drink anyway.

It was either at rest or moved at 10 m/s, depending on when the acceleration started.

No. It's e.g. a full moon because the moon is on the far side of the earth, and is fully illuminated by the sun. The earth is just rotating, letting us all see that. I think if you drew a picture you'd see this. ——— You can see the effect of the moon's effect on the earth, making the orbit "wobble," by looking at the time of aphelion and perihelion. Unlike the solstices and equinoxes, which basically advance 6 hours and then reset on a leap year (reflecting the extra ~.25 day in the year), the time of the aphelion and perihelion jump around, because the moon's orbit isn't synched up with the length of the year, and the location of the moon affects the distance to the sun.

v = at for constant a Object 1 accelerates at 1 m/s^2 for 10 seconds. Object 2 accelerates at 2 m/s^2 for 5 seconds. They will both have a final speed of 10 m/s. There are an infinite number of ways it can happen.

As has been pointed out, there's lots of water, but it's fresh water that is in short supply. Coastal areas have problems if they take too much water from the ground, as seawater will diffuse in and contaminate the aquifer. (Saltwater intrusion) http://www.olemiss.edu/sciencenet/saltnet/ http://water.usgs.gov/ogw/gwrp/saltwater/ But this is a local phenomenon. Depletion at one point will not cause this problem at a remote location.

One should realize that when a homework-like question is posted, the goal is to help the poster find the answer him/herself, rather than do the work for them.

And we're back to "All models are wrong. Some are useful." Saying that models aren't accurate is true; infinite accuracy and precision will never be achieved, but then, that's true of any scientific model, and some of them are certainly useful. You have to quantify what accuracy/precision/resolution is required of the model. Otherwise the objection is so open-ended as to be useless.

Oh, you can make Rb go boom. I've been working with alkalis for almost 20 years (they are the easiest to laser trap because of their simple state structure). There was one time we were cleaning out the oven used to create a Rb atomic beam, and thought all of the macroscopic bunches of Rb were gone. The oven was basically a pipe with a small hole in the side and a removable top; you'd drop a 5g ampoule inside, put it in a vacuum chamber and pump out the air. Well, the last time we had filled it, our postdoc had crushed the ampoule while trying to pop the top off (after scoring it with a glass cutter; he apparently didn't score it well enough) So there were a few small bits of glass in the oven, and some Rb was hiding underneath. When we dumped some water in to scavenge those last few atoms, it turned into a cannon and shot the glass into the side of the fume hood.

I think of it in terms akin to collapsing a wave function. You have a distribution that exists over all space, but you've made a measurement, so you get the answer for one particular location.

I can understand why some parents don't want their kids exposed to the books they want banned, too, so parental desire can't be the criterion. For me it comes down to the first amendment protection — if the speech is protected, you shouldn't be allowed to ban books containing it. If parents don't want their kids to read e.g. Harry Potter, then they should exert some parental control. Consider the cleaning bills. Would you want to borrow such material from the pubic public library? The poll is certainly not a scientific one. That's generally true of any poll that fails to promote anonymity or choose subjects randomly. The easiest division is to ban none of them. Then there is no debate over where to draw the line.

I think that conclusion was reached ~30 posts ago.

Once you postulate something that violates physical law, you can justify pretty much any answer you want to.