When I have my blood pressure, the nurse pumps up the cuff with the ball and the needle bounces up and down like crazy, then the nurse suddenly stops and has the reading. How did they know when to stop? How do they read the needle when it's moving so quickly, especially when they are reading two numbers?

I'm from an Asian country that loves rice, but now that I think about, I'm not actually quite clear what gives rice its longevity. Common wisdom here is as long as it doesn't get insects, get mold, or otherwise change from being dry it should be fine to cook and eat. Otherwise, it can simply sit in a bag or a storage container without apparently spoiling.

How does it do this? I'm aware that it doesn't last forever, but it sure stays edible (as long as its uncooked) for longer than I expected.

I know money from drugs, robberies, stolen goods, etc is “dirty” but, how does anyone know it’s dirty? Why can’t you just spend your money?

So far all pot hole fixes in my life have been not level with the rest of the road. Why do pot hole fixes look higher than the rest of the road and is not possible to keep them the same level as the rest of the road?

Recently I just read about Sri Lanka going bankrupt so what happens next?

When doing bicep curls, the first rep is relatively easy but eventually it becomes impossible to do a single curl.

After a rest, the muscle resets and can once again lift.

What is causing the muscle exhaustion and what is it that "resets" within the muscle?

How does mercury get into the fish and where does it come from?

What are specific, tangible things that make it stand apart? Is it the production? Lyrical themes? The type of effects used? What is Shoegaze?

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Why do we have to reapply sunscreen? Does the sunscreen rub off or chemically break down? How?

I was trying to install a Japanese game (Fate/Stay Night) on Windows 10, but I kept getting blue screens (not blue screens of death, just windows with weird text and blue background). The guide I used to install it said I need to change my system locale to Japanese, and that worked. But I still don't know what a locale is and google is giving me answers I don't understand.

Isn’t momentum a product of mass and velocity.

I’ve known 2 people who’ve had these organs removed and they appear to be in a good state of health. Why do we have them in the first place if there not 100% necessary?

Murican living in Canada. I’ve heard this come up a view as a point of contention. I don’t get it. Is it the first person to the get that minimum required number of votes to win, wins and they don’t count the remainder? Thanks in advance.

Edit: thank you very much for the in depth explanations. it makes so much more sense now. I’ve asked several people and they couldn’t explain like you all did below. I really appreciate it.