Ohmic Resistance Puns

So filament lamps are non-ohmic because if you increase the voltage across them then the charge carriers disipate more energy in the resistance of the lamp, causing it to heat up, increasing the resistance, and therefore reducing the increase in current with each increase in voltage. Therefore they are not proportional and therefore it is non-ohmic.

With an ohmic resistor, surely as current passes through the resistor, the resistor heats up and increases in resistance just like with the filament lamp and therefore not ohmic because the resistance is changing?

Or am I missing something?

Recently ive been diving into antenna theory and learned about gain. However theres some value that looks like an epsilon with a subscript of A i think and i dont know how to calculate it.

I have been struggling with a question that I cannot seem to make a good answer for. We know that the electrolysis of water to make hydrogen gas is not 100% efficient, but I am not sure what exactly is driving these loses in efficiency if it's not just the energy barrier that the reaction must past in order to be executed (because it is non-spontaneous) What makes electrolysis of water inefficient?

Hello everyone, for a project at my university i have to evaluate the temperature dependence of the electrodes of a DMFC. I have gathered the iv-plots for cathode and anode via a measurement with a standard hydrogen reference electode. Now i want to derive the exchange current density by Tafel-plotting my Data in Excel (i have got no other data processing program). Best case scenario is a rising exchange current density with rising temperture (at least thats what i think will happen out of "arrhenius-reasons"). So my question is, is the exchange current density a good/fitting indicator to explain the temperature dependence of both electrodes independently. As far as theory is concerned the current exchange density shows a strong temperature dependence. But does tafel-plotting the real life iv-plots for each electrode and temperature and deriving the current exchange density work. I tried Tafel-plotting my Data without any success till now, bit first things first.

For further insight: i am mainly focusing on deriving the current exchange density for the anode because it is the main reason for temperature dependence of the fuel cell according to my Dataset (i think this is beacuse of the methanol oxidation on Platinum-Ruthenium Catalyst being far more complicated and showing a bigger activation-overptential than the electrocatalytic ORR on Platinum and thus the anode is more volatile to a change in temperature than the cathode) So i want to compare i0 of the cathode and anode with rising temperature.

This is an academic post but it is something I've always found interesting because nearly every person in the world believes V=IR is Ohm's Law. But that is actually incorrect, read on to find out why!!

When asked what is Ohm's Law, you would probably say back V=IR, or an equivalent form of that equation such as I=V/R or R=V/I. And that is correct, Ohms Law is exactly "voltage through a conductor is directly proportional to the current through that conductor". So Ohm's Law is V=IR. But what is interesting is that this is actually a very strict definition. When two values are directly proportional, they are always directly proportional by the same value. This value is called the constant of proportionality. The constant of proportionality in this instance is the resistance of the conductor. So in other words what this means is as long as the resistance of the conductor doesn't change, then the conductor obeys Ohm's Law. But what happens when the resistance does change?

As we vapers know, when you pass electricity through a conductor, the conductor will heat up because of its resistance to allow electricity to pass through it. When some materials heat up, its resistance changes. Take a coil made of stainless steel for instance and say it has a resistance of 0.4 ohms at room temperature. When that coil heats up, its resistance will change (inceease). After firing for a few seconds, the coil may now be 0.45 ohms. (How much the resistance changes depends on how much the temperature increases). But what is interesting here is that this material does not follow Ohm's Law because the resistance is not constant (remember, the constant of proportionality cannot change). Stainless steel is called a non-ohmic material because Ohm's Law can't be used to model its behavior. If Ohm's Law doesn't work, what equation can be used to model electricity passing through it? We can still use V=IR. V=IR still works even if the resistance changes. So what does this mean? It means that Ohm's Law is V=IR but V=IR is not Ohm's Law. This is not a paradox, it's just a one way definition (doesn't work backwards). V=IR applies to every situation while Ohm's Law only applies when the resistance of the material doesn't change.

So what does this mean for vaping? Not much really, you still use I=V/R when calculating amp draw, but if you are using a non-ohmic material such as stainless steel or nichrome the coil resistance will slightly increase as it heats up

I don't want to step on anybody's toes here, but the amount of non-dad jokes here in this subreddit really annoys me. First of all, dad jokes CAN be NSFW, it clearly says so in the sub rules. Secondly, it doesn't automatically make it a dad joke if it's from a conversation between you and your child. Most importantly, the jokes that your CHILDREN tell YOU are not dad jokes. The point of a dad joke is that it's so cheesy only a dad who's trying to be funny would make such a joke. That's it. They are stupid plays on words, lame puns and so on. There has to be a clever pun or wordplay for it to be considered a dad joke.

Again, to all the fellow dads, I apologise if I'm sounding too harsh. But I just needed to get it off my chest.

Do your worst!

They were cooked in Greece.

I'm surprised it hasn't decade.

Don't you know a good pun is its own reword?

Two muffins are in an oven, one muffin looks at the other and says "is it just me, or is it hot in here?"

Then the other muffin says "AHH, TALKING MUFFIN!!!"

For context I'm a Refuse Driver (Garbage man) & today I was on food waste. After I'd tipped I was checking the wagon for any defects when I spotted a lone pea balanced on the lifts.

I said "hey look, an escaPEA"

No one near me but it didn't half make me laugh for a good hour or so!

Edit: I can't believe how much this has blown up. Thank you everyone I've had a blast reading through the replies 😂

It really does, I swear!

Because she wanted to see the task manager.

But that’s comparing apples to oranges

Heard they've been doing some shady business.

but then I remembered it was ground this morning.

Edit: Thank you guys for the awards, they're much nicer than the cardboard sleeve I've been using and reassures me that my jokes aren't stale

Edit 2: I have already been made aware that Men In Black 3 has told a version of this joke before. If the joke is not new to you, please enjoy any of the single origin puns in the comments

BamBOO!

They’re on standbi

A play on words.

Morning, Folks.

Summary: Our team is having troubles with temperature measurements of a system at LN2 temperatures. When tested by submerging in LN2, the RTDs report accurately, but when attached to the objects that they are intended to measure, they give non-physical values. These values plateau at temperatures that are both impossible based on the material properties and geometry and constant over very long periods of time implying that this is a steady-state. This behavior began after a long down period during which I rebuilt the object that is cold, but the RTDs themselves were only disconnected and reconnected.

We have, so far, disconnected them from the RTD module and directly measured the resistance to ensure that we are not seeing ohmic heating. The resistance agrees with the non-physical temperatures which should preclude problems with the module. We have removed, tested, and reinstalled the sensors and have gotten slightly different, but still very wrong results. During this time, we also looked carefully for heat leakage paths, but nothing is evident.

Details: The system is a double crystal monochromator (DCM) with a sandwich geometry of directly LN2 cooled copper, silicon, copper, silicon, copper with RTDs wrapped in indium foil and inserted into the holes in the ends of both silicon crystals. Other RTDs measure the temperature of the incoming and outgoing LN2 as well as various points on the assembly. The approximate dimensions of the cold mass are approximately a 6" cube. This cold mass exists inside a large vacuum chamber operating at ~10e-9mbar which serves as both the insulating vacuum and eliminates x-ray-air scatter.

The particular RTDs in which I am interested are those attached to the silicon crystals since they are their protection against over-temperature. For those who don't know silicon is a magical material at LN2 temperatures for two reasons: 1) the thermal conductivity is approximately that of diamond nearly 2000W/m*k and 2) the thermal expansion coefficient goes to (and through) zero. We operate this system with the surface temperature at the zero point to dramatically reduce the thermal strain from a high power and power density x-ray beam striking the crystal. Due to the easily achievable runaway condition of the thermal conductivity increasing with increasing temperature, these RTDs will trip off the beam when needed. Our machine is powerful enough to destroy these crystals easily enough.... Specifically, the RTDs indic

My daughter, Chewbecca, not so much.

Pilot on me!!

And boy are my arms legs.

Christopher Walken

Nothing, he was gladiator.

Or would that be too forward thinking?

Dad jokes are supposed to be jokes you can tell a kid and they will understand it and find it funny.

This sub is mostly just NSFW puns now.

If it needs a NSFW tag it's not a dad joke. There should just be a NSFW puns subreddit for that.

Edit* I'm not replying any longer and turning off notifications but to all those that say "no one cares", there sure are a lot of you arguing about it. Maybe I'm wrong but you people don't need to be rude about it. If you really don't care, don't comment.

What did 0 say to 8 ?

" Nice Belt "

So What did 3 say to 8 ?

" Hey, you two stop making out "

When I got home, they were still there.

I won't be doing that today!

Hindus, on the other hand, never had any beef.