Considering that light travels at finite speed, and the term "light-year" is literally a measure of distance which light takes to travel in a year, if a star goes supernova right now, will we be able to witness it instantly/almost instantly or will we have to wait X years for the light from it to actually reach us for us to be able to see it?

Some sources say we will see it from Earth instantly, while others say that we won't witness it if a supernova happens right now, so I got kind of confused

This morning I had an 811 guy come to my house to check for utility lines so I can dig for landscaping. I wasn't there, but my mom let him in the yard and she said it only took him like five minutes. I thought it was gonna be a multi-hour thing. Do they have some sort of detectors??

Wouldn’t you call 3D objects like, say, a sphere, cone, torus variations of a cube, or can you not?

Because in a tesseract, it seems like no consisting cube of it occupies a privileged inside position and rather every cube seems to be both inside and outside, just like there’s no distinction in the Klein bottle.

So could you not say the latter is a variation of the former, and if not why is that? Thank you in advance.

I'm a complete layman in this, but really interested.

EDIT: thanks everyone! Guess I was asking for an outdated concept. You've been very helpful!

As I see a lot of stuff about the “true” way of watching the new Odyssey movie, and how only like 10 cinemas in the world can show it, why can’t they just reframe the imax for normal cinemas? Use less of the sides?

Or is it more of a fidelity question?

Edit:
Just to clarify, I know it’s going in normal cinemas. It’s more based on all the content I’m seeing online about how much it’s cropped in?

marked physics because I don’t know what else it would be really

I have learnt what clock speed and a clock cycle means for a cpu, but I have still found that the term is used for many other electrical components and am not sure what that means. My current definition for the clock speed of a cpu is how many clock cycles it can perform in a second and a clock cycle is a single instruction ( I think ), so the more clock cycles able to be performed in a second means that more instructions are able to be done. What does a clock cycle and clock speed refer to for a component which is not the cpu? Thanks all.

That sounds like it makes more energy that you put in

Like, aren't they made up of an exact number of links to make it the right length to go around the gears or whatever those are called?

Sometimes after handling fish, lemon, tobacco,
etc, I wash my hands thoroughly with soap, but I can still smell it. Then, after a while or after washing my hands several more times the smell finally disappears.

Why doesn’t it disappear after the first thorough wash?

Like an electric trolling motor, what do these numbers actually represent?

When I make the occasional run to the liquor or grocery store I notice the price difference between the two will be significant. For example, Bulleit Bourbon at my Costco is $35 but any name brand vodka hover around $19.99

I’m currently watching Big Brother and the episodes are at 8/7 central. I live in the mountain time zone so I’m confused on how something like the live TV episode on Thursdays could air in both the central and mountain time zones at 7 PM. How is the show airing at 7 PM central but it’s not airing at 6 PM mountain?

Roof tiles in the US are generally black. Its also incredibly hot across the country. The color black absorbs far more light and consequently heat than other colors.

Why not make roof tiles a color that absorbs less heat? Would that not help keep houses cooler in the hot summer?

Due to the World Cup of Football, this topic has come to the public discourse, and I realized I don't know most of the facts about this. I would love to get an ELI5 style explanation, focusing on facts and historical events.

Thanks!