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Diners use cheaper ingredients, and don't throw any coffee out, while paying their staff much less than minimum wage.

Diners make their money on turnover; more customers across more of the day.

Car dealerships use the same cheaper ingredients as the diners, but yeah, the coffee is subsidized entirely as a perk, not a for-sale-item.

then why would people buy new cars every 5 years?

When delivering more current a given piece of metal heats up more. This is why you see warnings about not using flimsy extension cords for high current appliances like space heaters. A USB-C connector only needs to deliver up to 240 watts. A standard 120/15a outlet will go up to 1800 watts - so to keep the same reliable and safe temperature on your connector, those power-delivering terminals would need to be 7.5 times larger.

But yes, you could make a new connector that would be harder to make contact with accidentally. But then you’d need to convince people to swap out potentially billions of power outlets

You're so welcome!

The contact wires aren't exposed on the wall plug, they're protected inside the outlet

The plug that you're putting in isn't supposed to be energized until its mostly inserted and difficult to touch so the fact that its exposed metal normally is fine. Basically the reason male-male AC plugs are bad is because the violate the rule of keeping energized surfaces out of reach

Small interior pins that lay on pads struggle to carry any significant amount of current without overheating. For anything that you need to pump >8A through you really want a very firm connection which is generally a pin or equivalent with springy metal bits pushing on it from each side to ensure good contact

We do this with wall plugs, the prong slides between two bits of springy metal that ensure contact. High power test equipment uses similar pins that slide into spring contacts.

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Our bodies produce heat. We need to give off heat to maintain the right temperature. For most of us somewhere around 70 degrees F is the temperature where we are in equilibrium with the rate of heat we produce being matched with the rate we lose to the surroundings. When the air is 90 deg F we still lose heat but not quickly enough. This is why we sweat so that we can boost our heat loss through evaporation.

Humidity, air density, and wind all change the temperature at which we reach equilibrium.

We feel warm when our body needs to either produce less heat or dissipate it more efficiently (by sweating or changing the blood circulation pattern).

So we feel warm at lower than body temperature, when the natural metabolic rate of our body produces more heat that can be dissipated without extra effort such as sweating.

What we call feeling cold or warm is not a measure of the temperature, it is a signal for our body to modify behavior to keep its temperature constant.

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https://physics.stackexchange.com/questions/377814/why-do-we-feel-hot-when-temperature-is-relatively-high-even-though-it-might-be-l#:~:text=So%20we%20feel%20warm%20at,extra%20effort%20such%20as%20sweating.

Got it, thanks. Never really thought that it would be as simple as shielding the contacts like that.

If we can shield contacts in USB-C, why can't do the same with wall plugs. Is there any practical reason why the contact wires need to be exposed on wall plugs?

Knew someone with no sense of smell their entire life....they hated peanut butter because they said it was flavorless and felt like eating oily beach sand. its amazing how important the sense of smell is to taste

Coffeeshops are a striking example of this, as they have a very long history of functioning as a semi-public gathering space where people spend long periods of time relaxing, talking, working, reading, and so on. The price of a cup of coffee is really more like the price of entrance and the fee to stay there.

Thanks, So there's no feature verifying the wire is plugged or not like I suspected, the metal part is just neutral and the real hot contact is protected by the metal.

thank you!

My take away here is someone licking batteries.

If you believe in the Bible then you know that the soul enters the body with the first breath. A fetus does not have a soul, so the time in the womb doesn't count.

Besides, 'birthday' literally means the day you were born.

thank you! That article explains exactly what I was wondering.

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D’oh! I never was into hair metal after all.

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Spot on, except you mixed up the AC/DC. AC from the wall, DC through the USB

Take a random 10hr shift. Let’s say you get an 80% markup on your coffee, so while you charge $1.00 for it, you only paid .20c for actual coffee, and make .80c per cup. On a regular 10hr shift, you sell 200 cups of coffee which means you made $200 in revenue and $160 in profit. Well, not exactly. You pay your barista $11/hour, so now you actually made $49 in profit.

Now imagine you only mark it up 50% (.40c). You sell the same amount over the same shift. You’ve now made $80 in revenue and are already not making a profit because of payroll alone. And this isn’t including rent, utilities, supplies, etc you also have to pay. This is obviously extremely simplified but the point is that you have to make enough from the goods being sold to cover all expenses, not just enough to replace the goods. Coffee shops are not pulling 80% of revenue as profit; in reality, it’s probably more like 3-7% at best

Shipbuilders also had their own interesting wrinkle on getting enough air into the engine.

Late nineteenth century engines needed a big opening that the stokers could shovel in the coal. You couldn't pump extra air into the fire, because it would flow out too easily. The solution was to keep the entire engine room at high pressure with fans blowing air in from outside.

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