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Type: Posts; User: tk421

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1. ## Thread: How the circuit "knows" to change the current

by tk421
Replies
1
Views
170

### View Post

In exactly the same way that the circuit “knew” to make the current 10 amps with the original 2 ohm resistor.

You have to recognize that these are steady-state values. The current does not jump up...
2. ## Thread: Energy-momentum relation question?

by tk421
Replies
7
Views
1,469

So you added gamma after your initial post, but you didn't consider what that means. As Janus pointed out, when you actually use gamma, you are led to the mathematical absurdity I hinted at in my...
3. ## Thread: Energy-momentum relation question?

by tk421
Replies
7
Views
1,469

### Hint: What is the correct expression for...

Hint:

What is the correct expression for energy? Your original equation was not relativistically correct (I see you have edited it without comment; that is not good). Why not? What is this...
4. ## Thread: Energy-momentum relation question?

by tk421
Replies
7
Views
1,469

### So your question is: "If I violate the laws of...

So your question is: "If I violate the laws of physics, will the laws of physics still apply?"
5. ## Thread: Crystal Symmetry Problem, Conductivity tensor

by tk421
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1
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5,733

### Hint: Is there a relationship between band...

Hint: Is there a relationship between band structure and effective mass? If so, how might you use it?

by tk421
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4
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1,187

### You wouldn't expect to learn calculus in a forum...

You wouldn't expect to learn calculus in a forum post, right? Well, you shouldn't expect to master GR that way, either.

Get a copy of Misner, Thorne and Wheeler. It's over a thousand pages long....

by tk421
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13
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1,373

### The only cure for such ignorance is education....

The only cure for such ignorance is education. Unfortunately, the first step is to acknowledge that one's knowledge is deficient. You are confident in a way that is unjustified, and so it is doubtful...

by tk421
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5
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23,931

### A lot of non-scientists have this odd notion that...

A lot of non-scientists have this odd notion that audacity is missing. But if you attend any conferences, you'll see no end of far-out ideas. The thing is, the lay press generally don't attend these...
9. ## Thread: Gravity Violates the 2nd Law of Thermodynamics?

by tk421
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4
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1,031

### Perhaps it's because you have mistaken the first...

Perhaps it's because you have mistaken the first law for the second.

Of course no energy is "lost" -- that's what the first law says, and that's all you argue above.

The second law says...

by tk421
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13
Views
1,373

### Oh good. You can google after all. But you still...

Oh good. You can google after all. But you still failed the test: Helium doesn't yield protons when ionised!

But since you can google there's no need for my further tutoring of you. As they say in...

by tk421
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13
Views
1,373

### Sorry I don't offer free tutoring to lazy cranks....

Sorry I don't offer free tutoring to lazy cranks. Google for proton beam and heliarc welding.

Buh-bye.

by tk421
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13
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1,373

### Thank you for the offer. No doubt I need help in...

Thank you for the offer. No doubt I need help in a great many areas, but not in this thread. Your nearly incoherent post reveals that of the two of us, you are by far in greater need of a science...

by tk421
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13
Views
1,373

### Don't be ridiculous. A magnetic field accelerates...

Don't be ridiculous. A magnetic field accelerates any charged particle in motion.

Look up the definition for "justify." You seem not to know what it means.

Whether a magnetic field is...

by tk421
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7
Views
1,230

15. ## Thread: More and more people worldwide are reporting 'glitches' - events they've witnessed that violate the laws of physics such as people vanishing into thin air right in front of them, or walking through solid walls. What are your thoughts on this?

by tk421
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7
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1,230

### There are lots of sites on the internet, many of...

There are lots of sites on the internet, many of which contradict each other, so obviously the mere existence of a site doesn't automatically confer legitimacy on the idea being promoted. That's part...
16. ## Thread: Regarding Hg emission spectra

by tk421
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2
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1,251

### The LS coupling approximation is just that -- an...

The LS coupling approximation is just that -- an approximation. By its selection rules, the 253.65nm line would be forbidden (only triplet-triplet and singlet-singlet transitions would be allowed)....
17. ## Thread: How is going Respected Prof. Charles Kittel today?

by tk421
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3
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977

### I myself am not a particular fan of the Berkeley...

I myself am not a particular fan of the Berkeley Physics series of books, other than Purcell's, which is truly excellent. Kittel's contribution is perfectly serviceable, but conspicuously devoid of...
18. ## Thread: Does charge convert to heat or cause heat when passing through a resistor?

by tk421
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1
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896

### The motion of charge through a material involves...

The motion of charge through a material involves inelastic collisions, which is a fancy way of saying it bashes its way through the material, making the atoms in the latter vibrate. The energy...
19. ## Thread: Question about the length contraction and time dilation in the Special Theory of Relativity.

by tk421
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3
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885

### Look at the dimensional inconsistency in your...

Look at the dimensional inconsistency in your equation: L = v L0. That's one problem, at least.
20. ## Thread: Introducing myself - returning to physics after a long hiatus

by tk421
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1
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2,375

### Welcome to the forum, Gene!

Welcome to the forum, Gene!
21. ## Thread: Newton meter question- very confused

by tk421
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2
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1,704

### Because this is a homework question, we can't...

Because this is a homework question, we can't give you the answer. However, here are some suggestions:

1) Study the definition of "spring constant". Focus on what it means, not just a collection...
22. ## Thread: Current Voltage Filament Lamp

by tk421
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15
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1,938

### I've explained it twice now, and you seem to be...

I've explained it twice now, and you seem to be determined to ignore it.

Both V/I and dV/dI are resistances. There is therefore not a unique R. You seem to think there is only one definition of...
23. ## Thread: Current Voltage Filament Lamp

by tk421
Replies
15
Views
1,938

### Your opinion is wrong, as explained to you with...

Your opinion is wrong, as explained to you with reasoning by me and AndrewC.

A standard linearisation technique in science is to compute the first derivative of a nonlinear quantity. That quantity...
24. ## Thread: Current Voltage Filament Lamp

by tk421
Replies
15
Views
1,938

### Yes, and again, that question, as phrased without...

Yes, and again, that question, as phrased without additional context, is too ambiguous to admit a unique answer. The writer of that question apparently did not understand that there are multiple ways...
25. ## Thread: Current Voltage Filament Lamp

by tk421
Replies
15
Views
1,938

### Your question is ambiguous because you haven't...

Your question is ambiguous because you haven't specified for what purpose one is to use the answer. Without that additional information, there is no uniquely correct answer.

If, for example, the...
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