Recent comments in /f/askscience

agate_ t1_j7f6jdb wrote

Not by much. Thermal conductivity in gases happens by molecules gaining thermal energy and moving to a colder place. Adding more molecules gives you more energy carriers, but they can’t move as far before bumping in to each other. So the thermal conductivity of most gases increases only slightly with pressure.

If you get near the boiling point, or the pressure is so low the molecules fly the length of your chamber without bumping into anything, the situation is different.

https://www.electronics-cooling.com/1998/09/the-thermal-conductivity-of-gases/

https://www.engineeringtoolbox.com/amp/air-properties-viscosity-conductivity-heat-capacity-d_1509.html

https://www.engineeringtoolbox.com/amp/methane-thermal-conductivity-temperature-pressure-d_2021.html

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ellipsis31 t1_j7f4giw wrote

Infrared and red laser pointers are direct laser diodes (put current in and light squirts out). Green and blue laser pointers are made by using an infrared laser diode to pump a nonlinear optical crystal which doubles the frequency (halves the wavelength... however you want to say it) to put out photons with a new color. That doubling leaves a gap of wavelengths that are more difficult to access.

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meellowstar OP t1_j7f43ax wrote

Thank you very much everyone for answering in such detail and with so many different approaches! You guys are awesome! Different time zones for each city thats crazy to imagine. How different the people lived and thought about things in the past compared to us nowaday, even different perceptions of time. I'm going to finish my thesis now. But it was a blast reading all of your answers and theories.

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Cyber_Fetus t1_j7euwdi wrote

I’m speaking for Mandarin here as I know it and assuming it applies to at least most other tonal languages.

To avoid complication of different levels of whispering and whether the lack of vocal chord vibration can be compensated for through other means, even with a complete lack of tones the listener could still easily use context clues to understand provided they’re fluent enough in the language. For this reason non-native speakers of tonal languages can often get by using incorrect tones or no tones at all.

If you remove tones, any given word still only has a limited number of other words that would overlap. For an English example, though “bought” and “bot” are pronounced the same [Edit: in at least one major US accent], you distinguish a speaker’s use of one versus the other through context.

There is however likely a higher chance of misinterpretation or confusion, say if I pointed to a tree and said “songshu” contextually both “squirrel” and “pine tree” could fit, but these instances wouldn’t be super common and you could likely just ask for clarification.

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RexRauron t1_j7esprm wrote

Fat is stored and metabolized all the time. Hormones like insulin determine at which rate these processes occur. When more fat is available then the body needs, more fat is stored then released.

Btw most of the fat we store is from our diet. Converting carbohydrates to fat is ineffective and only contributes a very small amount under normal conditions.

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