Recent content by Skaperen

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    Question about the voltage between two charged capacitors

    there is no A1-B2. i am wondering if a charged capacitor can be treated as having an electrostattc charge. not the whole capacitor, just one terminal on each (A2 and B1).
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    Question about the voltage between two charged capacitors

    suppose you have two capacitors with a 0.1 Farad value and 12 VDC rating. label these as A and B. label the terminals of each as 1 and 2. you also have a voltmeter with a 40 volt linear range for DC. you also have a 9 volt DC power supply fed by mains. you charge each capacitor to 9 volts...
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    I Color and appearance of a "pile" of biological viruses

    Normally, an electron microscope would be needed to "see" a biological virus or other objects of this size scale because they are so much smaller than wavelengths of light we can see with our red/green/blue sensitive eyes (700 nm down to 400 nm) at any magnification of an optical microscope...
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    Python Python Socket library to create a server and client scripts

    many OSes can run process performing both server and client work at the same time (multiplexed so fast humans believe them to be simultaneous). i could name these OSes, but you already know them.
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    Looking for a chemical with a boiling point between 10C and 50C

    i am looking for a chemical compound that has a boiling or condensation temperature between 10C and 50C at standard pressure and is not one prohibited for discussion in the Physics Forum or any online chemical forums. something that is organic and not very toxic is preferred. it should be...
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    I What Direction Do Sparks Travel from Steel-on-Steel Friction in Railroad Wheels?

    when a railroad engine wheel slips on a rail as it tries to move forward i can see sparks mostly going in the rear direction. while thinking about what might happen in other situations, such as a moving engine (being pushed by its massive 100 car load, perhaps), i came to a simplistic case that...
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    I Relative Speed of Light Between Objects

    This is one of my thought experiments where I am drawing a big blank, If you have 2 objects approaching a 3rd object from opposite directions (just enough off to avoid collision) at 75% of the speed of light, the first assumption is that each observing the other would see the other object...
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    How are step-up/step-down transformers wired?

    That would not be an issue on step-UP where the supply has an SGC/neutral. But clearly there is a complication if the supply has no SGC/neutral. I guess in such a case you don't get to use that exception since its requirement cannot be complied with. No. Since the need for the step-down is...
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    How are step-up/step-down transformers wired?

    They list only two ways to make such a transformer, yet there are three ways. The difference between these is that the grounded isolation method connects the neutral side (has the wider blade hole) of the 120 volt output to the ground wire itself, inside the transformer. It seems from their...
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    How are step-up/step-down transformers wired?

    In a colocated rack cabinet supplied with ONLY 208 volt power, and a requirement to follow electrical codes that include not permitting NEMA 5 type power outlets with 208 volts on them, we need to supply power to a device that has a "wall wart" transformer with NEMA 1 type (North American flat...
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    How are step-up/step-down transformers wired?

    No wires coming out except for the cord with the plug. There is usually one of those universal sockets, and maybe one additional one for North America.
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    How are step-up/step-down transformers wired?

    Really? How would one do that? These are supposed to be sealed boxes with outlets, not standalone transformer components.
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    How are step-up/step-down transformers wired?

    Autotransformers are less safe for a couple reasons. One is that they depend on the including live conductors for ground reference, and in particular need to have the side that is common on "primary" and "secondary" (quotes because that's not exactly a correct terminology for an...
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    How are step-up/step-down transformers wired?

    I see a lot of these transformers that claim to do both step-up and step-down in the same unit. At least one had a photo of the back side and there was a switch labeled to set it according to the input voltage. What I am curious about is how these are wired. Are they isolation transformers or...
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