1

Technology / Re: Can you explain this demonstration of a capacitor?

« on: 22/03/2023 23:26:43 »

you'd need a battery-powered microammeter floating at around 1000 V to show the effect - not a common piece of kit.

Not common.
But there's one in that video.
The Keithley 602

https://download.tek.com/manual/29111C(Model602).pdf

2

COVID-19 / Re: can i have a full run down on spike protiens please?

« on: 18/03/2023 22:10:46 »

I think Ebola has spike protein
https://www.reuters.com/article/health-ebola-dc-idUKN0937961120080709

, are they god/bad/neutral

From the viruss perspective they are very good.
From the patient's point of view, they aren't.

3, how are they made

The same way a virus makes any other protein; they hijack the biochemical pathways of the cells they infect.

4, do they occur naturally

Yes; they are part of many viruses.

5, if they are bad, how do we get rid of them

Our immune system destroys them (if we are lucky)
To completely eliminate them I think we need to wait until the sun goes red giant and bakes them all.

3

Physiology & Medicine / Re: How important is penis size in regards to the actual sex act?

« on: 16/03/2023 14:01:35 »

"How important is penis size in regards to the actual sex act?"
Not very.
Ask any lesbian.

4

Chemistry / Re: Can glucose be synthesized without organic inputs as sources?

« on: 14/03/2023 12:33:12 »

I seem to be missing something.
What was the purpose of this thread?
You asked a question
Can glucose be synthesized without organic inputs as sources?
And immediately answered it

Answer seems Yes. Synthesis without organic inputs.

Nature Magazine, 1887.
https://www.nature.com/articles/037007b0

You made a statement that looks like it might be a question in disguise.

What is the latest development. Is this synthetic glucose considered a "food", digestible.

I don't know what the latest developments are but glucose is glucose is glucose. Of course you could use it as food.

Somehow, the base substance to synthesize glucose must come from a source that traces back to an organic material.

That depends on your definition of organic but, in any event the laws of physics say that you can make compounds from the elements.
Your assertion about where it traces back to is simply wrong.

My main question is that, despite our advanced state in science and technology, we are still unable to synthesize genuine food from the basic fundamental elements

Your "main question" is a false statement.

It seems we are not able to "defeat" the creator of living things. 

That just shouldn't be on a science page, should it?

You can't sensibly say you came here to ask us about the topic because, when I told you I got this

Question: Show me a DEFINITE link that  acrolein may be synthesized from acetylene.

It's not actually a question; it;';s just an assertion that when you get an answer you don't like, you refuse to believe it.

I admit I have lost.

Lost what? The plot?
This isn't meant to be a competition; it's meant to be a discussion.

5

Physics, Astronomy & Cosmology / Re: Do you change the spectrum of radiation inside an oven if you change its shape?

« on: 12/03/2023 18:11:55 »

As (almost) always, the answer is "it depends".
The emission line from a laser can be subject to "mode hopping" because, as its temperature changes, the wavelengths reinforced by resonance also chance. The Fabry Perot resonator depends critically on the size and shape of the cavity.

With a black body cavity, the light can't know how far way the other side is, and the spectrum depends on the temperature.

If I get a box with mirror walls and put a police car in it with the lights flashing, that light is still blue.

6

Chemistry / Re: Can glucose be synthesized without organic inputs as sources?

« on: 12/03/2023 16:47:27 »

Living things have an element that is beyond the reach of physical laws of nature.

The evidence says otherwise.

Google search gives no definite answer if  acetaldehyde and formaldehyde may react to give acrolein.

Then it's just as well you can ask a chemist, isn't it?
However, I'm a little puzzled you you couldn't get Google to confirm what's said on the WIKI page about acrolein.

"The original industrial route to acrolein, developed by Degussa, involves condensation of formaldehyde and acetaldehyde:

HCHO + CH3CHO → CH2=CHCHO + H2O"

Show me a DEFINITE link

OK, you want a link to a page where a competent, qualified chemist tells you that it can be done?

https://www.thenakedscientists.com/forum/index.php?topic=86170.msg700727#msg700727

7

Physics, Astronomy & Cosmology / Re: Do you change the spectrum of radiation inside an oven if you change its shape?

« on: 11/03/2023 22:32:49 »

So Planck was wrong after all.

No, he was right, which is why he didn't say what shape or size the cavity was; he knew it didn't matter as long as it was black.

8

Physics, Astronomy & Cosmology / Re: Do you change the spectrum of radiation inside an oven if you change its shape?

« on: 11/03/2023 11:53:23 »

if we look inside an ideal carbon spherical shell* at red heat, the tiniest surface imperfection will alter the Planck resonance spectrum by adding or subtracting wavelengths equal to arbitrary multiples of the height of the imperfection,

No, it won't.
That's why (or because, depending on how you look at it) they use graphite; it's black.

You can not get cavity resonances if the walls are black.

9

New Theories / Re: If there was one Big Bang event, why not multiple big bangs?

« on: 11/03/2023 11:41:24 »

I don't assert any new idea.

That's true. You assert ideas that were dismissed many years ago because they don't tally with the evidence.

10

New Theories / Re: If there was one Big Bang event, why not multiple big bangs?

« on: 11/03/2023 11:40:25 »

before the Big Bang.

A phrase that makes a little sense as "north of the North pole".

11

Physics, Astronomy & Cosmology / Re: Do you change the spectrum of radiation inside an oven if you change its shape?

« on: 10/03/2023 13:36:57 »

To a good approximation*, an electron in the wall of the oven which drops to a slightly lower energy level (and emits a long wave photon as a consequence) does not know what shape and size the oven is.

Waveguides are often silver plated or even lined with superconductors to improve the sharpness of their frequency response.
A black body is  (pretty much definitively) not.

The analogy isn't  getting a resonance from a flute; it is trying to play a tune on an exhaust silencer. (I might pay good money to watch someone try to do that.)

If the wall opposite absorbs all the radiation which hits it, there's no way for the radiation to "know" how far away it is.

It's not a good approximation if one of the walls is a good mirror.
I did some pointless research on this as a student. You can change the half life of fluorescence by putting the emitter near a mirror.
But you don't make black bodies out of mirrors so it's beside the point.

12

Physics, Astronomy & Cosmology / Re: Do you change the spectrum of radiation inside an oven if you change its shape?

« on: 10/03/2023 11:45:01 »

I'm not sure it's possible to tell.
I think we are looking at the idea that wavelengths comparable with the length of the side of the box will be perturbed by the size and shape of the box.


If I get a metal box (like a microwave oven) and put a tungsten light bulb in it. the light doesn't get out.
If I make a small (say 1mm) hole in the wall, the light gets out and I can measure its spectrum. The box hardly makes a difference to that.
I can, also measure the infra red from the lamp.

In principle, the bulb also emits microwave and radio wave radiation.
But I can't see them- not because the box changes the spectrum of the lamp, but because the long wavelengths will not pass through the small hole.
The longer than about 1mm wavelengths are filtered out

So, I can only observe the spectrum of what's happening in the box through a filter which I know removes anything with a wavelength longer than 1mm.
If I make the hole bigger (comparable with the size of the box) in order to look at wavelengths comparable with the size of the box then...
it isn't a box any more.

13

New Theories / Re: If there was one Big Bang event, why not multiple big bangs?

« on: 08/03/2023 15:55:57 »

Therefore, why do we insist on 13.8BY as some magic number?

Because that's what the evidence says.

14

Just Chat! / Re: An Open Statement To Atheists...

« on: 07/03/2023 13:03:55 »

. But Christian's are at least still courteous and polite.

This is a science site.
We deal in evidence.
Judged on the evidence, your assertion is plainly false.
https://en.wikipedia.org/wiki/Catholic_Church_sexual_abuse_cases

You might have got away with sating "most Christians..."
But of course, the reply to that is "Most atheists...".

So, all you did was say something that was plainly wrong.
And then you have the audacity to say

As I said, I'm sorry I had to say that. But it's true.

You should be ashamed of yourself.

15

Just Chat! / Re: Should we tip our physicians when they do a good job?

« on: 06/03/2023 14:56:36 »

I read somewhere that the ancient Chinses paid their doctors when they were well, and stopped paying if they got ill.

16

Just Chat! / Re: Empty words?

« on: 04/03/2023 12:13:20 »

Can you describe a nonexistential crisis for my enlightenment?

For the fish in my tank, a failure of the air pump is an existential crisis. It threatens their existence.
For me the rise in fuel costs is a crisis, but it won't kill me.
It is not an existential crisis.

17

New Theories / Re: What is the real readshift in the Cosmic Microwave Background (CMB)

« on: 04/03/2023 00:20:41 »

Sorry, you have a fatal mistake!

I'm not dead.
You clearly are wrong.

18

Geology, Palaeontology & Archaeology / Re: Why do insects fly?

« on: 03/03/2023 17:59:26 »

The entire  "why did that evolve?" question seems to come down to the usual thing:   There was a niche available and random mutations seem to be sufficient explanation for why life generally evolves to fill all available niches given time.

19

General Science / Re: In controlled demolitions, what procedures are applied to prevent air toxicity?

« on: 02/03/2023 14:49:54 »

They take the asbestos out before they demolish the building.
Most buildings are not really toxic- apart from sand which is carcinogenic.
If buildings were actually toxic they would poison the people inside them. That's rare but I have heard of it happening.
The wrong grade of chipboard gave off a lot of formaldehyde.

It's also helpful to avoid filling the building with jet fuel and setting it on fire.
People typically manage that.

20

Physiology & Medicine / Re: How important is it to geld a horse?

« on: 23/02/2023 17:53:34 »

Tell us you don't understand how aggressive an intact stallion is without saying "I don't understand how aggressive an intact stallion is".