Recent content by drummin

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    I Pixels Per Inch Calculation Paradox?

    aneikei, are you trying to measure something with your camera?
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    Generating Audio Signals from Lasers: Theoretical Possibilities?

    Your nano antenna would convert the light EM wave to an electric signal just like a radio antenna. The laser light electric field alternates as with any real photon, so the EMF on the antenna will alternate the same way. Problem is this electrical signal would travel a very short distance...
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    What is a magnetic field "made" of?

    Photons are carriers of the EM force so must be involved with the DC magnetic field. The creation and collapse of the DC field certainly creates photons, with a very long wavelength component.
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    Is sum centrifugal force and centripetal force zero?

    Centrifugal does not exist in a non rotating frame of reference. So you can have centrifugal or centripetal force acting on the ball depending on which frame of reference you choose, rotating or not, but no both together.
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    Why do manufacturers use a gas that emits UV light in fluorescent light bulbs?

    Other gasses have 2 problems. They don't produce white light and they generally need much higher maintaining voltages. They use mercury because, after warm up, it has a lower impedance so needs less voltage. The high energy UV, or at least blue, photons are needed to excite the phosphors thus...
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    Math Class: Necessary or Redundant?

    Congratulations annoyinggirl, never stop reading and indeed you could become proficient in higher math. However, I have always contended that math and science education depends on the oral tradition of teaching. In spite of having easy access textbooks, the vast majority of people cannot...
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    Where do positrons come from in the production of EM radiation?

    A photon is NOT made up of an electron and a positron. Really, drop that idea, it is leading you to wrong headed problems. 511keV photons are a very special case.
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    Where do positrons come from in the production of EM radiation?

    There are no positrons involved with the creation of the vast majority of photons. Your EM wave/photon stream is created by electron motion alone. The electron-positron creation-annihilation involve only high energy gamma ray photons of a specific energy (511 keV) and are quite rare as photons go.
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    Drift velocity and charging a capacitor.

    Yes, the drift velocity is quite slow but there are a lot of electrons in the "electron gas" of the metal conductor.
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    Solving the Solar Panel Debacle: Powering a 6V Battery with 4V Cells

    Not much would happen. Your solar cell output is a million times smaller that a typical AGM battery capacity of 200 amp-hours. A quick calculation 200amp-hours/1.8ma = over a million hours of charge time with the cells in series. The battery has more internal leakage than that.
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    Can Air Really Block Our View of the World?

    You can see air quite easily by looking at a daytime blue sky. Although it is apparently quite transparent the scattered blue light overwhelms the dimmer star light, at least to our eyes. So you can see air, but you need many miles of it and good lighting.
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    How Can a Near Object Be Focused While Looking at Distant Objects?

    A small convex (magnifing) lens does the trick. For example an prismatic compass uses such a lens to allow the user to view the moving compass card (a couple inches from the eye) and a landmark in the distance (miles away) at the same time for accurate readings.
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    Why does light bend when it passes through different mediums?

    I like the water analogy. In elementary physics we experimented with a wave tank, a large flat tray with an with about 1/2 inch of water. Half the tank had a flat spacer to create a shallow area with a step ledge to the deeper side. Then a wave generator (electric motor vibrating a wood stick...
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    Infrared as Heat Waves: Why Only IR?

    I always thought they are called heat waves because the black body radiation from hot household objects such as a pan on a stove peak at the infrared wavelengths. "Heat waves" is an archaic term from kitchen experiences.
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    Three-phase power explained using water/electricity-analogy?

    Water flow in a pipe does have an analogy for magnetism around a current carrying wire, At least in the transmission line sense. The momentum of the moving water causes similar effects to magnetism around a conductor. For example when a flow in a pipe is quickly shut off at the output end the...
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