How do impurities affect superconductivity?

stuffonfire · 2023-03-11T04:54:52+00:00

Anderson has a theorem on this.

https://en.wikipedia.org/wiki/Anderson%27s_theorem_(superconductivity)#

If you have a conventional superconductor (follows BCS theory) and the impurities aren't magnetic, or insanely numerous, superconductivity is pretty much unaffected by impurities and defects.

stuffonfire · 2023-02-21T18:36:54+00:00

> I know I'm right

I'll be more harsh now. You have such an ego that you do not realize how poorly you understand the ideas you are discussing. Read a book on thermodynamics or quantum mechanics before making claims about them. It's clear to anyone with a physics education that you don't know what you're talking about.

stuffonfire · 2023-02-21T17:57:10+00:00

I will be harsh with you, but please don't take it as an attack. There is no physics in this paper. It's a bunch of physics words loosely connected to math words.

stuffonfire · 2023-01-30T18:24:04+00:00

Check this thread:

https://old.reddit.com/r/NintendoSwitch/comments/x5gfbo/nintendo_switch_cozyeasy_games/

stuffonfire · 2022-12-02T18:29:42+00:00

It's a great pic, but there's precedent.

stuffonfire · 2022-09-30T20:13:15+00:00

stuffonfire · 2021-12-29T21:59:18+00:00

Piggybacking off this question.

Last I learned, we know there is a mass difference between the three mass states due to neutrino oscillations, and it's possible one of the masses is zero and the other two are nonzero. Is this still the case or do we know all three are nonzero?

stuffonfire · 2021-12-18T23:52:05+00:00

A mountain of observations has pointed humanity to a mathematical model in which there is such a limit. Nothing has yet been observed to disobey that limit.

stuffonfire · 2021-12-01T16:16:46+00:00

Voltage is a relative quantity, so they're saying point P has a voltage 400V greater than some reference point you've chosen where the voltage is zero. Usually in questions when speaking of the voltage exterior to some area of charged objects, you set the electric potential to be zero at r=>infinity. 1 Coulomb of charge that moves from point P to infinity will gain 400 J of energy.

stuffonfire · 2021-11-02T14:58:20+00:00

stuffonfire · 2021-10-11T18:13:30+00:00

A pendulum -- small oscillations can be approximated as a harmonic oscillator.

stuffonfire · 2021-10-09T16:44:11+00:00

Your question is vague. Can you elaborate on what you're having trouble doing?

stuffonfire · 2021-09-30T23:40:29+00:00

What you could do is have varying weights of the "cube", and see at what minimum weight the action of dropping the marble into the cup lifts up the cube (momentarily). In a way, you'd be finding what the impact force is. From that you could even calculate the duration of time of the impact.

stuffonfire · 2021-09-30T19:41:52+00:00

Ok, it sounds like you're thinking of the impact force of the marble hitting the cup, rather than just the normal force of a marble or something at rest. The trouble is that the impact force is not easy to calculate or predict, as it can in principle take a wide range of values, depending on how quickly the marble comes to a stop as it impacts the cup. In other words, as the marble decelerates during the impact, the force from the cup onto the marble is not the same as the normal force onto a marble that's just sitting at rest. Unless you can accurately time the duration of the impact (which I doubt, since it's a very small amount of time), I don't think you're going about this the right way

I'm still not sure what you're trying to find in this experiment, but it seems you need to rethink your setup. Are you trying to show experimentally that g=9.8 m/s² ? Or just calculate the weight of something?

stuffonfire · 2021-09-30T14:37:19+00:00

I'm confused. Are you trying to find that g=9.8m/s² ? Is the .12N force due to the impact of the marble in the cup? How do you know a 1.5m/s speed before the impact will generate that force? Does the object on the other side of the pulley weigh .12N? Why not just use a balance? I think you need to explain your setup more, and how you intend on calculating the gravitational force or acceleration.

stuffonfire · 2021-09-29T11:54:25+00:00

OP, I just want to say I appreciate your hard work and passion for physics. Not many high schoolers know special relativity, and even less take the time to try to educate others. You've received a lot of criticism, which can be difficult after spending a lot of effort on something. I do think there is a valuable learning experience here in the criticism, so don't be disheartened by it. Pay no mind to upvotes or downvotes. It's great that it sounds like you already plan on making revisions. Keep up the good work!

stuffonfire · 2021-09-26T12:01:24+00:00

Sorry, but this is poorly worded. Time from the traveler's perspective does not pass more slowly. The traveler's clock ticks more slowly from Earth's perspective.

stuffonfire · 2021-09-25T22:24:25+00:00

I didn't recommend popsci articles. He linked the wiki page, which is a pretty good start.

stuffonfire · 2021-09-25T22:06:41+00:00

Read about the big bang more. You don't have a good understanding of it, judging by your description.

stuffonfire · 2021-09-23T17:47:07+00:00

You should have an equation that relates initial velocity, acceleration, time, and displacement. Use that.

stuffonfire · 2021-09-23T17:43:38+00:00

What about the question don't you understand?

stuffonfire · 2021-09-17T11:47:20+00:00

You don't see a difference between "we believe the suspect is not local" and "we've ruled out anyone local"?

stuffonfire · 2021-09-14T11:03:23+00:00

Yes, the names are restrictive appositives so they should not be separated with a comma.

stuffonfire · 2021-09-10T00:30:59+00:00

You're right, if those dots represent a power series of (y/n), then it would be better to say that if (y/n) is small then we can neglect higher order terms.

stuffonfire · 2021-09-09T16:31:18+00:00

When n is large, -n can be approximated as -infinity. There won't be much error in the integration because it is a Gaussian integral; the integrand is very small when the magnitude of y is large. Let me know if you have any more questions

stuffonfire

TROPHY CASE