Why do circuit breakers go up for on and down for off?

Feb 11, 2023 Last reply: 2 years ago 1839 Replies

I had a friend with a PhD in electronics who might have had a problem with it. A full circuit analysis taking into account the internal resistance of the battery and so forth would be easy.

He wasn't quiet that bad although he lived in his head and not the physical world. One day he demonstrated why you shouldn't put a random piece of wire across the terminals of a car battery to see if it is dead. Spoiler: it wasn't.

Sort of, I guess. I stick with my meter for diagnosing AA batteries. The JND* between the wet finger circuit and just licking the positive terminal is minute.

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Clearly not, as you're reading my posts. Don't lie, it makes you look like a fool.

Then curve them the other way you idiot. I can't believe how stupid you are. There's nothing magical about one direction, perhaps you beleive it's something to do with the earth's rotation? If so, maybe they work the other way in Australia?

Every video I can finds has them rotating clockwise. Obviously from the front, why would you look at it from the back when the blades are at the front? You wouldn't say a clock goes anticlockwise because you view it from the back.

It would be very unlikely for a cat to happen to dial 1 repeatedly.

I doubt there are many of them. The emergency services could then just phone the phone company to get it sorted.

Superfluous word.

We aren't as stupid as the EU, imposing laws for others to follow.

Why didn't you unplug the phone? Or change the number on your phone exchange?

My smartphone allows (as I think they all do) anyone to dial an emergency number without unlocking the phone. I've denied them that priveledge by replacing the standard lock screen. If you want to phone the emergency services, use your own f****ng phone.

Mine (before I had a smartphone) used to dial the first person in the address book regularly. To unlock the phone you only needed to hold one button (the one in the corner) for 3 seconds. Which happened when I leaned against something with the phone in my pocket. I guess there was some other shortcut for speed dial. I felt sorry for the friend I kept dialling, so I put in a fictitious entry, for some company who kept spam calling me.

How can you confuse a 4 and a 9?

Our directory enquiries charge a fortune to put you through to another number. But it's free if you just write down the number. Most of the workers actually tell you to do this....

How can people remember all those numbers? I only remember the emergency number, and the slightly less emergency number. But I can never decide how much of an emergency it is. If your neighbour is keeping you awake at 4am and you want to phone the police, do you dial 999 or 101? It's not life and death, but it does need responded to now, not after he's stopped doing it.

If I was suicidal, why would I want someone to stop me doing it?

Nasty. A teacher at my school, 40 years ago, had a blotchy face and bald patches in his hair. He told us that he'd been working on his car some years before and a spanner slipped and shorted across the battery terminals. The battery exploded, showering him with acid. Luckily he wore glasses which shielded his eyes from getting acid in them. Nowadays car batteries have a plastic shroud around the terminals to make it very difficult for a spanner etc to touch both terminals (or the +ve and a grounded part of the car) at the same time.

Broadly speaking, yes.

Modern houses in the USA are probably more fire resistant, and you have a fire department.

These are quite a recent invention.

In the Great Fire Of London, over a square mile of wooden houses was completely destroyed. 100% attrition.

We lose

That is today, we were talking about 'traditional' houses. Structurally it looks like 700 years is possible with wood. But several thousand with stione or brickk. .

At least in the US the default is to dial 911. The pizza was cold when the guy delivered it? Dial 911. Working in a PSAP (public-safety answering point) is not a job I would want. Interspersed with calls from assholes, you deal with violent crimes in process, mass casualty incidents, hostage situations, and family members watching Pop die. You never know until you pick up the damn phone.

A room temperature IQ helps. All them numbers is just white supremacy.

Like many companies we sometimes had summer employees that happened to be related to someone up the hierarchy. One managed to explode the battery on a forklift trying to jump start it. Fortunately he wasn't injured. Returning a vice president's favorite son worse for the wear isn't a good career move.

I know someone that does just that. Some odd people calling for odd things. Recent one was a woman calling from her apartment. This is at

4AM. "There is a satellite dish on the roof and it is not needed. Please send someone to take it down"

Precisely so.

with tone dialling its a cinch

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