[alancalverd]

Graham's Hierarchy of Disagreement

Calverd's hierarchy of disagreement
1. State case
2. set out counterarguments
3. how many lives/how much money at stake? If none, continue, else go to 8
4. agree the critical experiment
5. do the critical experiment
6. review critical experiment
7. agree - go to end
8. take the less dangerous or if equally dangerous, less costly route
9. evaluate
10 agree - go to end.
11. end - shake hands, write down and remember the answer.

If neither lives nor money are at stake, and there is no critical experiment, do something important instead of arguing.

[hamdani yusuf (OP)]

The black/white video skated over the elephant in the room! Skin temperature is regulated by perspiration and blood flow,* pretty much independent of ambient, if your clothing is reasonably insulating - which a robe certainly is because it traps a lot of air.   


*blood being cooled by evaporation in the lungs if the external skin surface is insulated.

I've seen other videos using black and white balloons. Black balloons exploded when the beam of a burning laser pointer hit them, while white balloons survived.
So, we have seemingly contradicting results.

[Bored chemist]

we have seemingly contradicting results

It only seems that way to you.

[alancalverd]

I've seen other videos using black and white balloons. Black balloons exploded when the beam of a burning laser pointer hit them, while white balloons survived.
So, we have seemingly contradicting results.

It all goes back to the basis of thermodynamics. The hotter body will always lose heat to the colder body, but

the rate of radiative exchange depends on the surface "color"

the rate of conductive exchange depends on the conductivity of the intervening material

the rate of convective exchange depends on the convective heat transfer function of the carrier, which is a function of umpteen variables of chemistry and geometry.

But the result is always the same.

Laser heating was proposed in the Sixties for drilling caries out of teeth. Healthy enamel is highly reflective  but decayed material tends to be brown or black and thus strongly absorbent, so you can ablate it with an optical laser.   

[hamdani yusuf (OP)]

Laser heating was proposed in the Sixties for drilling caries out of teeth. Healthy enamel is highly reflective  but decayed material tends to be brown or black and thus strongly absorbent, so you can ablate it with an optical laser.   

It can also be done using sunlight.

[hamdani yusuf (OP)]

we have seemingly contradicting results

It only seems that way to you.

It also doesn't seem contradicting for anyone who doesn't know them, or doesn't want to think about them.

[Bored chemist]

It also doesn't seem contradicting for anyone who doesn't know them, or doesn't want to think about them.

It doesn't seem contradictory for anyone who thinks about it (because the explanation is obvious), or for anyone who does not think about it (because they don't notice anything odd).

So, it seems that you  are the only one who sees a contradiction.
Can you tell us what that contradiction is?

[hamdani yusuf (OP)]

It also doesn't seem contradicting for anyone who doesn't know them, or doesn't want to think about them.

It doesn't seem contradictory for anyone who thinks about it (because the explanation is obvious), or for anyone who does not think about it (because they don't notice anything odd).

So, it seems that you  are the only one who sees a contradiction.
Can you tell us what that contradiction is?

The clothes aren't felt different, but the balloons reacted differently. At least an explanation should be provided to have caused the difference.

[Bored chemist]

At least an explanation should be provided to have caused the difference.

It was.

Skin temperature is regulated by perspiration and blood flow,* pretty much independent of ambient, if your clothing is reasonably insulating - which a robe certainly is because it traps a lot of air.   

Now, I accept that there are other factors involved (for example, windspeed), but none of them is "unknown to science".
So there's no "contradiction" here, just different circumstances.

[hamdani yusuf (OP)]

At least an explanation should be provided to have caused the difference.

It was.

Skin temperature is regulated by perspiration and blood flow,* pretty much independent of ambient, if your clothing is reasonably insulating - which a robe certainly is because it traps a lot of air.   

Now, I accept that there are other factors involved (for example, windspeed), but none of them is "unknown to science".
So there's no "contradiction" here, just different circumstances.

Science is not just imagining what could cause observed results. It's called hypothesizing.
Scientific investigation aims to eliminate wrong hypotheses by confronting them with related observation results.

How do you think wind speed change the results for black and white balloons?

[Bored chemist]

Scientific investigation aims to eliminate wrong hypotheses by confronting them with related observation results.

Do you not understand that such observations have been made?

How do you think wind speed change the results for black and white balloons?

Enough air blowing past the balloon might stop it heating up enough for the rubber to soften and might stop it bursting.
Did you not realise that?

[hamdani yusuf (OP)]

Enough air blowing past the balloon might stop it heating up enough for the rubber to soften and might stop it bursting.

Do you think that eliminating wind would make black clothes feel hotter than the white one?

[Bored chemist]

Enough air blowing past the balloon might stop it heating up enough for the rubber to soften and might stop it bursting.

Do you think that eliminating wind would make black clothes feel hotter than the white one?

It depends on other things, like whether the sun is shining, how brightly, and how windy it is.
Are you unable to understand that something may be due to a combination of factors?

But none of those is unknown to science.
There is no contradiction.
You were simply wrong when you said this

So, we have seemingly contradicting results.

[hamdani yusuf (OP)]

It depends on other things, like whether the sun is shining, how brightly, and how windy it is.
Are you unable to understand that something may be due to a combination of factors?

Do you understand how they combine to produce observed results?

[Bored chemist]

It depends on other things, like whether the sun is shining, how brightly, and how windy it is.
Are you unable to understand that something may be due to a combination of factors?

Do you understand how they combine to produce observed results?

Yes thanks.

[hamdani yusuf (OP)]

But none of those is unknown to science.
There is no contradiction.
You were simply wrong when you said this

So, we have seemingly contradicting results.

Do you realize that words are written to convey a meaning?
Someone somewhere may already know the answer. Do you?

[hamdani yusuf (OP)]

It depends on other things, like whether the sun is shining, how brightly, and how windy it is.
Are you unable to understand that something may be due to a combination of factors?

Do you understand how they combine to produce observed results?

Yes thanks.

You can keep it for yourself, or share it with other forum members here.

[alancalverd]

I think anyone who has studied physics or survival skills will know the answer.

There have been a few "solar hot air balloons" that used a black envelope to enhance lift; google   Bristol 2015 Solar Balloon for a good one that also exploits "white" fabric on the downsun side to minimise heat loss. And note that the  checkerboard pattern on many NASA rockets is designed to control solar heating and radiative cooling as the craft rotates.

[Bored chemist]

You can keep it for yourself, or share it with other forum members here.

It's not a secret; but the answer is "it depends" which seems to upset some people.
But I'm curious.
Did you not realise that the answer was going to be "it depends"?

[hamdani yusuf (OP)]

You can keep it for yourself, or share it with other forum members here.

It's not a secret; but the answer is "it depends" which seems to upset some people.
But I'm curious.
Did you not realise that the answer was going to be "it depends"?

Depends on what?