Recent content by .Scott

  1. .Scott

    What happens if shielded cable has short to the shield?

    It wasn't clear enough for me. So, what you are describing is a cable that is not connected to any circuit at all. It is just a length of cable sitting on a bench with shielding applied. Or a similar length of shielded cable sitting on a store shelf. We will also assume that this shielding...
  2. .Scott

    What happens if shielded cable has short to the shield?

    The "to nothing" part was basically a typo. The signal source will be shorted to ground, the same ground as the shielding. So, that will be the end of your signal. @Baluncore described how this kind of cable is used. The purpose of having the shielding fully encircle the core is to protect...
  3. .Scott

    What happens if shielded cable has short to the shield?

    It's worse than that. A single shielded cable normally expects the return current to pass through the shield. The shield will often be connect to the circuit ground or perhaps even the chassis ground. So at the signal source end, the signal will be grounded - possibly resulting in an...
  4. .Scott

    I Question of accuracy of galactic collision simulations

    Which, of course, will limit the usefulness of the discussion. I think you are over-stating how much friction is involved. Wherever there is substantial and immediate friction, there will be enormous heat. The overall contribution of friction to the dynamics of the first "moments" of the...
  5. .Scott

    Struggling to understand the concept of this question (ice cube in water optics question)

    When dealing with Physics assignments, I am willing to assume everything is frictionless, there are no aerodynamics, and things like levers and ropes are massless. But putting an eye or camera underwater is a different matter. We need to be explicit about what constitutes a "vanilla" camera -...
  6. .Scott

    Struggling to understand the concept of this question (ice cube in water optics question)

    What is significant about looking down from above is that you are looking at the water through a horizontal surface between the air and the water. Looking up through such a horizontal surface will produce the same effects.
  7. .Scott

    Struggling to understand the concept of this question (ice cube in water optics question)

    The reason I didn't think the problem would be set up this way is that now you are using a lens system intended for air and putting it in direct contact with the water. This drawing also clears up another issue - "long" means "high". Do we get to assert that any reasonable human observer would...
  8. .Scott

    Struggling to understand the concept of this question (ice cube in water optics question)

    Are you quoting the problem statement precisely? If so, we are supposed to presume that this ice cube is a real cube - and therefore, 10 cm high. Once again, the phrase "from the water" is very ambiguous - it could mean from the surface of the water or from beneath the water surface or from...
  9. .Scott

    Struggling to understand the concept of this question (ice cube in water optics question)

    I believe the author intends for the observer to be looking down into the water from above the water. There is enough information provided in the problem statement. You should have been given an equation for computing the actual depth given the apparent depth when viewing down through a...
  10. .Scott

    Will-o’-the-Wisps

    I read the article. .. So we can have ignition. For methane, the concentration in air needs to be between 5 and 15%. So, presumably it starts out near the surface at a high concentrations, then drifts upwards to where a flame is sustained. I think we still have a few dots to connect.
  11. .Scott

    Urgent: Physically repair - or bypass - power button on Asus laptop

    It doubt that a USB keyboard will do it for you. But that video that @Rive linked to is spot on. And the tool that I suggested was certainly in the ball park. The person in the video is not using a wrist strap. But I'll bet the humidity in his room is pretty good (>50%). I wouldn't open up a...
  12. .Scott

    Urgent: Physically repair - or bypass - power button on Asus laptop

    Did the power switch have a different feel to it than the other keys? And how did it operate? If it was my problem and I needed to get power to it right away, at this point I would be poking around with this tool:
  13. .Scott

    Urgent: Physically repair - or bypass - power button on Asus laptop

    I am looking at other photo of the Asus keyboard. It's not obvious from the photos exactly how the contact is made. For example, this one: I am not convinced that is a straight electrical contact.
  14. .Scott

    Urgent: Physically repair - or bypass - power button on Asus laptop

    Looking at the part of the switch still connected to your machine, I see a metal plate about 15mm wide and 8 mm high. From the photo, it appears to have a bump in the middle that is recessed below the level of the plate. But from your recent remarks, I may be misinterpreting the photo. If it...
  15. .Scott

    Urgent: Physically repair - or bypass - power button on Asus laptop

    I noticed something else. There appears to be a fiber at the 11:00 position of the button part still attached to your machine. If that happens to be conductive, it may be shorting something. I would brush it away.
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