Recent content by ruko

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    Personal Jet Boat Water Craft Thrust Question

    I'm not asking the PWC to pretend, just you to pretend because there are those who will erroneously bring up drag changes and angles, etc. Really doesn't have anything to do with my question: Does the thrust increase or decrease?
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    Personal Jet Boat Water Craft Thrust Question

    Assume a jet boat or personal water craft (JetSki, etc) has a movable propulsion nozzle. This nozzle can be moved vertically so that the water jet driving the boat forward can be either above the surface or below the surface of the water. Further clarification. You are speeding along on your...
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    What causes flux to suck-in solder?

    If the oxide layer on copper pipe is not removed mechanically before soldering the joint will most likely leak.
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    What causes flux to suck-in solder?

    When soldering copper pipe you must remove the oxide layer first with sand paper or what ever. Needed is a bright shiney oxide free surface. Perhaps it is a reduction in surface tension that draws the solder in.
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    B Skydiving from Space -- maximum altitude?

    I asked about a figure skater arms in vs arms out velocity.
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    Demystifying the Often Misunderstood Bernoulli's Equation - Comments

    All those formulas. I don't have a Pizza hut Delivery to my name so they could be mean anything. What I really would like to know is the Bernoulli affect the main reason why airplanes can fly? If it is, then I wonder how airplanes are able to fly upside down.
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    Open circuit voltage of an old battery

    There is current flow in a voltmeter, certainly not much but some. A teeny tiny bit, micro amps I would guess. So it really isn't an open circuit with a volt meter across it.
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    Gulf Oil Leak: Explaining Pressure & Calculation

    I just attempted to answer your question. I did not infer you said anything! I think it is not perfectly correct to say that the pressure that forces air out of a balloon is mostly due to ambient air pressure compressing the balloon. I think a combination of both with the much larger edge going...
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    Gulf Oil Leak: Explaining Pressure & Calculation

    Internal pressure mostly due to the elasticity of the balloon material.
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    Understanding the Relationship Between Electric Current and Radio Waves

    If, in this case, "The larger the frequency" means higher frequency then the above statement is wrong. Increasing the frequency means a smaller or shorter antenna.
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    Improving Power Factor with Inductive Ballasts in Fluorescent Lights

    What do inductive ballasts, like those used in fluorescent lights, do to power factor?
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    Calculating resistance from voltage drop

    Measure the voltage across the resistor, then I = E/R. Now you know the current through the circuit if it is a series circuit. Measure the voltage across the light bulb, then apply R= E/I.
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    Power Loss in Cables: Is My Friend Correct?

    How is characteristic impedance of a transmission line determined? Disregarding shielding and interference possibilities which line is better for carrying a TV signal, 73 ohm coax or 300 ohm twin lead?
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    Being shot by a bullet in space. Damaging? Why/why not?

    I fired my modern 9 MM Luger autoloader several times holding it upside down and it worked just fine. What modern fire arm uses gravity to eject and reload a cartridge?
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