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1
Physiology & Medicine / Re: Why am I allergic to chicken and turkey?
« Last post by Don_1 on Today at 10:12:43 »
This is some ]fowl trick of nature, if you'll pardon the pun.

Its odd that your allergy seems to have taken a 1 month vacation and a separate 1 day vacation.

Perhaps it is not the chicken, but rather the cooking process or cooking additives.
2
It is rather odd that as we age, the hair on our bonce seems to slip down to parts where hair never grew or at least never gave cause for concern in our younger days.

I do find that the occasional stray hair can tickle my ear and there is little quite as unsightly as a forest emerging from one's snout.

Pluck it!

No, no, I haven't made a spelling error there, nor tried to cover up an expletive. I mean as I write. Pluck it. Its far better than cutting it. The problem goes away for that much longer. I do find displaced hair growth a tad annoying at times, but not exactly distracting.

But I have come to the conclusion that these hairs do serve a purpose. As we age, we become grumpy and these annoying hairs provide us with something else to gripe about.

Isn't mother nature wonderful! She thinks of everything, right down to our apparent love of finding things to moan about.
3
Just Chat ! / Re: Punning is hard(ly) work! Groaning aloud here?
« Last post by Don_1 on Today at 09:31:34 »

Just create a signage index and write it on the middle of your pinky so you won't forget it.


By Jove, I think you've hit the nail on the head there Demo. It certainly has a ring of good sense about it.

Will you be offering further good advice, or will you wrist your case there. If need be, I can always throw you a life line.
4
Quote
why when an object is condensed g [the acceleration due to that object's gravity] goes up

It is important to measure g under the same circumstances, ie measured at the same distance between the centers of the two objects.
  • The Sun's gravitational acceleration at a distance of 150 million km (center-to-center) pulls the Earth into an orbit of 365 days.
  • If you now compress the Sun into a neutron star 10km across, the Sun's gravitational acceleration at a distance of 150 million km (center-to-center) still pulls the Earth into an orbit of 365 days. ie the Sun's "g" is unchanged.
  • If you now compress the Sun into an even smaller black hole, the Sun's gravitational acceleration at a distance of 150 million km (center-to-center) still pulls the Earth into an orbit of 365 days. ie the Sun's "g" is still unchanged, despite the fact that it is now a condensed object.
  • The Sun's surface gravity is about 27 times that of Earth. This applies at a radius of 700,000km from the center of the Sun.
  • If you compress the Sun into a neutron star or black hole, the gravitational attraction at a distance of 700,000km is still 27 times that of Earth.

I think that the OP may be asking about why the surface gravity of a neutron star is greater than the surface gravity of the original star. This is because it is possible to orbit to within 10km of the center of a compact neutron star, but you can't approach closer than 700,000 km to the center of the original, more diffuse star.

Newton's inverse square law says that the gravitational force is much stronger at 10km than at 700,000 km.
5
Beware of assembling large stacks of cells that aren't designed for such assembly! You can get away with 10 x AA NiMH cells in series because in the event of one failing open-circuit the voltage across it will only be 10.8V. But if you put 40 cells in parallel and one fails short-circuit, the prospective fault current through the dud cell is several hundred amps and more than likely to burn a hole in your boat.

Face it, lead-acid batteries are crude, oldfashioned, heavy, but extremely robust, tolerant and reliable for high current demand. There's a good reason why they are the only approved technology for most small planes, and judging from the problems Boeing are having with Dreamliner batteries, I'd rather have a PbAc in a boat than anything else right now. 
6
Physiology & Medicine / Is this cleaner safe to use?
« Last post by Atomic-S on Today at 06:23:20 »
While using a common household powdered cleanser on a bathroom fixture, I became aware of its odor, and that it appeared to be being blown in my face by the direction of air currents in the room.  Then I noticed that the cleanser contains limestone and feldspar.  A number of mineral dusts have been found to lead to lung cancer or other lung diseases.  It appears that those who use these cleansers must frequently inhale dusts from them. Are they safe?
7
Just Chat ! / Re: Punning is hard(ly) work! Groaning aloud here?
« Last post by demografx on Today at 05:26:51 »

I wish I knew English sign language, it's pretty handy.



I was going to give you a few examples, but I don't want you think I'm trying to palm you off.

As I don't use sign language as a general rule of thumb, I am finding it hard to put my finger on the correct signage.


Just create a signage index and write it on the middle of your pinky so you won't forget it.

8
If mass has no affect on acceleration then why when an object is condensed g goes up. The radius is reduced but the mass is the same. A neutron star has the same mass as an equivalent uncompressed object but exerts a greater pull. Therefore shouldn't a condensed object falling in the gravitational field of the earth exert a greater force and therefore a different g?
9
Physics, Astronomy & Cosmology / Should the gluon have mass?
« Last post by jeffreyH on Today at 00:38:31 »
The gluon is considered massless but due to its short-range nature shouldn't it have mass?
10
The mysterious of nuclear power
From physics we know that the nuclear force is mediated by gluons, among the quarks inside nucleons. Argument why they do that, we do not know. According to the decision of physicists, each nucleon consists of three quarks in three different "colors" (owing to W. Pauli princip) so that at any moment, the resultant additive "color" of nucleon was "white". This fancy physicists causes to gluons has a  considerable organizational difficulties: to preserve that nucleon in all the time is "white", because colored nucleon is quickly fall apart.
Quarks can therefore be exchanged between the colored gluons infinitely quickly, if possible, at the same time. So if, for example, "green" quark transmits green gluon (nobody knows where?) must at the same time (!) "red" quark send his „red“ gluon to the former "green" quark, so that the three colors of quarks remain constantly maintained! This exchange must be implemented immediately, ie in null time!  Who manages this exchange? Well, at the two quarks would perhaps like to work. But, convey the current exchange color gluons between the three quarks is impossible!  We just have to hope that the sending quark somehow (?) finds out where the accepting quark is correctly located and sends his gluon toward directly at him. What is the ratio of captured and uncaptured gluons by? Thing, however, is more complex: the red quark to which gluon goes with a green branch  , must recognize in advance the intention of green quark, she is preparing for a exchange  at the same time to send him his red gluon. At that moment both quarks have no color! This assumes that the red quark in advance knows that the green quark, just sent to him his green gluon. Otherwise, he might send him   blue" gluon and it's fall to bummer; colored nucleon  fall apart In other words, physicists assume that quarks constantly know their color and their location in the kernel space and also the color and location of their "teammates" even if it is, according to physicists, constantly changing (no one tells you with what speed) and transmit to each other the right gluons. (It's hard to say what is in the kernel dominant? Whether the demand or offer. And what causes the quark to send his gluon?). So quarks apparently had both a quality  superfast detector of his location and the detector current state colors of quarks, or otherwise nucleons exist!
With this ‚technical equipment‘  should perhaps go handle color interaction of two quarks, but in each nucleon quarks are  the 3 quarks. A big problem here arises: What does a green quark when heads to him together with their colored gluons remaining two quarks: red and blue? Simultaneously sends to both quarks the gluons with right colors? At that moment, nuclear physics  probably does not exist. The nucleon  must somehow cope, with it,  when this  the "smart" physicists invented! Physicists have determined that  would be best if the gluons were an 8-color type .. Let's not forget that the "colors" are not true colors as we perceive them. It is in fact a distinct physical properties (such as the mass, spin, or electric charge), which, however, the lack of imagination of physicists do not have real physical name, so they will help out with colors. And they go so far as to talk about the resulting "white" color nucleon as if it were a true projection of  real color spectrum.
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