Recent content by Dale
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High School Electric Fields inside Conductors & Gauss' Law
It is not generally true that the E field in a conductor is 0. It is only true in the electrostatic limit where the current density is zero.- Dale
- Post #6
- Forum: Electromagnetism
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Undergrad Why is water pressure increased in a plastic bag in a bucket?
This sounds like the most likely hypothesis. It could be tested by comparing a bag with trapped air and a bag with all air removed. It would also be interesting if the bag without air got an air bubble from the air originally inside the clay.- Dale
- Post #33
- Forum: Classical Physics
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There are people in biology who really do math
Investigating the history of math or the philosophy of math is not exactly the same as using math. A more convincing reference would be something e.g. where a mathematical model is used to predict the contents of missing historical documents, or mathematical models to establish authorship. I...- Dale
- Post #3
- Forum: Biology and Medical
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Undergrad Why is water pressure increased in a plastic bag in a bucket?
If you have a sous vide you could test temperature dependence. Room temperature and residential water temperature can fluctuate. I don’t think that variable has been adequately controlled- Dale
- Post #9
- Forum: Classical Physics
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Undergrad Why is water pressure increased in a plastic bag in a bucket?
Could it be a temperature difference? 18” of water is about 0.05 atmospheres, so it is some pressure but not a lot.- Dale
- Post #2
- Forum: Classical Physics
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Undergrad Capacitor Voltages at t = 0: Zero or Split?
The Laplace transform also has the same issue. If we take the Laplace transform of the equation above we get $$0=\frac{V_0(s)}{R}+(C_1+C_2) \ s \ \left(V_0(s)-v_0(0)\right)- C_2 \ s \ \left( V_I(s)-v_I(0) \right)$$ This expression depends on ##v_I(0)## which is undefined and ##v_0(0)## which is...- Dale
- Post #15
- Forum: Classical Physics
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Undergrad Capacitor Voltages at t = 0: Zero or Split?
The ideal circuit has no real solution. The voltage at ##t=0## is undefined. Yes. Does that not clue you into the fact that the original circuit is inconsistent? LLM output is not a reliable source. It hallucinates. A Dirac delta is undefined at ##t=0##. You cannot make any definite statement...- Dale
- Post #13
- Forum: Classical Physics
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Undergrad Capacitor Voltages at t = 0: Zero or Split?
Yes. The equations for the original circuit have no real solution. So it makes sense that it wouldn’t simulate without R2. Yes, I showed that above.- Dale
- Post #7
- Forum: Classical Physics
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High School True static equilibrium and effects on time
You are currently truly still in your reference frame. How do you currently perceive time?- Dale
- Post #5
- Forum: Special and General Relativity
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Undergrad Capacitor Voltages at t = 0: Zero or Split?
In your sim you added R2. This is perfectly reasonable to do, but it is no longer the circuit that the argument is about. Once you add R2 there is a solution, but I don't think that you have resolved the argument about the circuit in the OP. You have just resolved a circuit about which there was...- Dale
- Post #5
- Forum: Classical Physics
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Undergrad Capacitor Voltages at t = 0: Zero or Split?
@Baluncore is right. If all of the components are ideal then the resulting system of equations has no solution. This is an “irresistible force meets immovable object” type of problem.- Dale
- Post #3
- Forum: Classical Physics
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High School Does acceleration affect impact energy vs constant velocity?
I think my post 24 gets them as far as they need for the simplest example that doesn’t “simplify away” the thing they are interested in. It is as simple as possible, but not simpler. -
Simple problem with voltages
It looks like ##V_{AB}=0## to me since they are directly connected by a wire. Is the triangle for ##I## just supposed to represent the direction of the current or is it supposed to be a current source?- Dale
- Post #2
- Forum: Introductory Physics Homework Help
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Undergrad The Electric Displacement, ##\mathbf D##
That is just a matter of the choice of units. In Heaviside Lorentz units all three quantities have the same units which is even more convenient than moving the constant around. https://en.wikipedia.org/wiki/Heaviside%E2%80%93Lorentz_units- Dale
- Post #2
- Forum: Electromagnetism
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Paul Hinds has passed
Oh, no! Thank you for letting us know, Robert. Your dad was amazing and I will miss him- Dale
- Post #19
- Forum: Feedback and Announcements