this post was submitted on 18 Mar 2024
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[–] [email protected] 32 points 9 months ago (3 children)

Watt and volt are two different measures for electricity. Also your fridge will not work when hooked up to a car battery for many other technical reasons, including differ t voltages, and current types (AC/CD, not the band)

[–] [email protected] 22 points 9 months ago (2 children)

That’s wrong. Watt is a measure of power and volt measures….. voltage.

Charge (electricity) is measured in Coloumbs (sp?)

You need a complete circuit for Watts as P=iv.

I is current, measured in amperes

[–] [email protected] 3 points 9 months ago (2 children)
[–] [email protected] 13 points 9 months ago (2 children)

Tautologists study tautology tautologically.

[–] [email protected] 4 points 9 months ago

The first rule of tautology club is the first rule of tautology club.

[–] [email protected] 2 points 9 months ago

The first rule of tautology club is the first rule of tautology club.

[–] [email protected] 8 points 9 months ago (1 children)
[–] [email protected] 9 points 9 months ago (2 children)

Another way to think of it is this: Volts are like water pressure (potential energy) Amperage is like the flow rate of water Ohms (resistance) is like how hard it is to push water from high pressure to low pressure Watts are like the volume of water (a unit of energy)

A big hose has low resistance, water can move freely A coffee straw has large resistance, it's hard to pull and push water thru it

A river has very low water pressure, and the speed of the water can vary, so volume of water moving can be huge so the flow rate of water can be huge as well. A pressure washer might have very high pressure, but use as much water as a kitchen faucet. Certain applications need high pressure, some need low pressure. A car battery is like a river, low pressure (typically 12volts) but move a lot of amps (cold cranking amps of up to 500-600 ish usually), and a wall outlet by comparison is like a pressure washer with 120v, 15A (in the US). A fridge won't play nice on 12v, it needs 120v. It might need 400 watts which a car battery can do but it cares about how it can get that by requiring higher potential.

A watt, W=VA, can be thought of as asking how much water is there? 1 minute under a sink verse 1 minute in front a fire hose has two very very different amounts of water.

A watt hour, which most people are familiar with in the US for billing on their utilities, is like asking how many cups of water an hour. A light bulb needs a fraction of a kilowatt hour, a drier needs multiple kilowatt hours, but might only run for 30 minutes.

This idea gets a little tricky and falls apart at its edges but as a general idea should hold up for most peoples understanding of electrical stuff unless you work with it daily like an electrical engineer, electrician or something similar. For sanity sake I'm not going to try to apply this to AC verse DC, I don't have a good analogy for that

Obligatory mobile formatting heads-up and what not and I'm not caffeinated so meh

[–] [email protected] 5 points 9 months ago (1 children)

Ugh, you’re getting into the realm in which technicality is hard to explain.

That’s technically wrong. Even though ampere is coulomb/sec, electrons don’t actually flow.

[–] [email protected] 6 points 9 months ago

Like I said it falls apart on its edges but for most people it's probably a better understanding of it than they will ever have or need, but most people scrolling thru Lemmy probably don't need to be understanding electrical concepts like electrons not actually flowing, charge, etc. I'm a controls engineer and while I am aware of the concepts and such, I am not designing electronics so at the end of the day I barely have a use for half of the concepts myself. Sure I could get down to the half semester class of quantum where things get weird, but that won't easily tell people to not to try to plug their fridge into a car battery

[–] [email protected] 4 points 9 months ago (1 children)

For the AC/DC part, I usually try to tell people it's like a water wheel that's been inserted into the hose of water. DC is it spinning one way constantly, while AC is it spinning back and forth. The wheel is turning pretty much the whole time (again, we can try to not be super specific with the way we do phases with AC), and thus you can use it to do stuff on AC or DC.

[–] [email protected] 4 points 9 months ago (1 children)

Clever, it just breaks down again with my analog of water volume lol. Definitely not saying it's wrong, I just like to leave it off so there are less questions haha

[–] [email protected] 3 points 9 months ago (1 children)
[–] [email protected] 2 points 9 months ago

And to turn dc into ac, you need to rotate a small singularity around the pipes of electricity. That's why inverters are so heavy

[–] [email protected] 3 points 9 months ago (1 children)

With the river analogy, Voltage = pressure, Wattage = how much water is passing, Current (Amps) is how wide the river is.

Pressure * Width of river = Amount of water passing

Not sure that helps with passing it through the terms and then to variables.

[–] [email protected] 3 points 9 months ago

Water analogy works better with plumbing. A river, not so much. But people aren't that much better at understanding plumbing, unfortunately...

[–] [email protected] 6 points 9 months ago (1 children)

Unless you have an electric car that can do vehicle to load. That means that you can plug in regular household devices like your fridge.

[–] [email protected] 15 points 9 months ago (3 children)

That vehicle isn’t using a traditional 12v car battery for that. Also the point t is you can’t connect a car battery to a fridge and expect it to work.

[–] [email protected] 8 points 9 months ago* (last edited 9 months ago) (1 children)

Unable to delete so editing instead. Leaving Lemmy.world due to privacy concerns.

[–] [email protected] -1 points 9 months ago (1 children)

Yes. That not the “use a12v battery” assignment. It would be use an inverter…

[–] [email protected] 6 points 9 months ago* (last edited 9 months ago)

Unable to delete so editing instead. Leaving Lemmy.world due to privacy concerns.

[–] [email protected] 2 points 9 months ago

Not with that attitude!

[–] [email protected] -1 points 9 months ago (1 children)

So. The answer is yes you can. If the car is an EV with V2L. Which I am guessing is what that uncle was talking about in the post.

[–] [email protected] 3 points 9 months ago (2 children)

V2L doesn’t relies on traditional 12v battery…

[–] [email protected] 2 points 9 months ago

Okay. But it's a car. Full of batteries.

[–] [email protected] 0 points 9 months ago

Correct, but entirely besides the point.

[–] [email protected] -3 points 9 months ago (1 children)

Unless you have an EV with V2L.

[–] [email protected] 13 points 9 months ago (3 children)

Sure you can use the 12v battery and convert that power but you can’t just connect a 12v battery and expect it to work.

[–] [email protected] 1 points 9 months ago* (last edited 9 months ago) (1 children)

You stated that you cant connect a car battery to a fridge. You said nothing in your comment about 12v. I can connect my car battery to my fridge no problem.

[–] [email protected] 2 points 9 months ago* (last edited 9 months ago) (1 children)

You can but it won’t keep your fridge cold. (Unless you use an inverter and you would need to check the amps needed by the fridge when the pump is on and see if your battery and inverter can provide that.)

[–] [email protected] 2 points 9 months ago

As i stated I have V2L on my car. I also have normal outlets inside the car.