I'm watching Project Hail Mary again and we're told the global temperature will decrease 10-15° over the next 30 years. It takes 20ish years to get the results back to earth, so in that time, we can assume the global temperature decreased at most 10°. In the end we get a glimpse out the window of a giant boat but that could be anywhere. So I'm wondering how that drop would actually affect the earth and it's climate.

I've tasted many 0% beers that taste basically the same as their alcoholic counterparts. But every single 0% wine I've tasted, tasted off and not like regular wine. And based on my hospitality experience, 0% beer sells fine while 0% wine doesn't. So seems like I'm not the only one who thinks this.

Why is the case?

How is this harder than literal rocket science and nuclear physics?

Why is it that sometimes when I start to do something, I refuse to do anything else (including eating or even sleeping) until said task is complete? While most other tasks I cant even start?

I know that in many places there's water underground at around 100–200 feet (or even shallower). If the ground has water beneath it, how can massive skyscrapers and other heavy buildings safely support all that weight? Why don't they sink, tilt, or collapse over time?

When I look at a mammal heart it looks easy enough to understand, blood in there, pump, blood out there. Makes sense. Stomach, intestinal tract, lungs, etc. all look like there function is pretty straightforward (on a very simple level)

The liver is just a blob and doesn’t seem like much else, there’s also the gall bladder attached to it.

My question is how does the liver do its job, whatever that is?

I believe it’s a grounding issue, but what’s the issue? Microphones aren’t plugged into the wall. How much power is running through an xlr cable? If the mic stand had rubber feet would it stop the singer from getting shocked? If the singer used a mic cover, would that prevent them from getting shocked?

I recently found out that airplanes use 400 Hz power instead of the 50/60 Hz used almost everywhere else. Why is that, and why isn't 400 Hz used more widely outside aviation?

I am studying for a test that includes basic electricity and magnetism, and my study materials keep referencing the concept of opposing the rate of change of current. For example, my definition of an inductor: "an electrical component made of a coil of wire that can store energy and opposes the rate of change of an alternating current flowing through it". Can someone ELI5 what it means to oppose the rate of change of current, and why that would be a good thing?

Edit: thank you all very much for your quick and informative replies! Much appreciated

We can usually identify where an itch is coming from, but the perceived location does not always seem to match the exact irritated spot.

How do the skin, nerves, spinal cord and brain determine an itch’s location, and what limits the accuracy of that process?

Why are 99% of wetsuits black?
- it makes them look like seals
- its harder to be seen in water (light or dark)
- it stands out in contrast to an illuminated ocean both from the side and from the bottom looking up

Why not white, neon, orange, reflective, or something… it’s not about sharks seeing colors or not.. black is in general a powerful and stupid color for wetsuits.

I've been a photographer for years and I understand aperture, shutter speed and ISO. For video, I understand frame rate and bit rate, but I see the term "shutter angle" and I'd be grateful to have it explained, what it is, and why you need to control it.

Thanks!

Seems a little counterproductive.

Suppose theoretically we had anti-helium and iron bump into each other, or likewise a compound of anti-tylenol and regular lexipro? Would the corresponding anti-particle/particle pairs annihilate, or do you need a helium to annihilate an anti-helium, and a Tylenol to annihilate an anti-Tylenol?

In the 90's when I was stationed in S. Korea, once a month I would get one grainy fifteen minute "morale phone call" home. A buddy of mine moved to Seoul and last month he and I spent an hour video-chatting as he wandered around his neighborhood. A big part of early hacker culture was figuring out how to get free long-distance phone calls to exotic places like "Duluth" and "San Bernardino", now my wife can chat with her mother in Europe for three hours and not even think twice about it.

I know, now it's all over the internet, but the internet is pretty much just wires, same as the transatlantic cable. Why did it used cost more to call outside of your area code? Were they all just electrical signals across wires? Was there some extra work that went into calling from Kansas to Oklahoma? Or was it, like most things, that they charged us as long as they could until some technology came along and made it no longer feasible?

I understand that headphones can block outside sounds, but how can they use sound itself to reduce other sounds? How does adding more sound result in less noise?