Recent content by ford2go

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    Voltage and Electromagnetic power

    First your flash circuit must put out enough power. It can be changed to a magnetic field regardless if it is high voltage or high current. There is a second consideration -- total energy. The flash circuit puts out a burst of energy. This will determine if it can drive the field for a long...
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    What happens, when you are trying to magnetize some iron bar?

    Just a few comments -- hopefully helpful. 1. As I'm sure the links state, applying a stong magnetic field to a ferrous material will magnetize the material. This is done because it forces all of the magmetic domains to align. In ferrous materials, once the external magnetic field us of...
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    How Can You Weaken the Strength of a Standard Magnet?

    Actually, if you shield one pole of a magnet, you might get what you want. Shielding is a misleading term. The shielding material ( which can be anything ferrous -- depending on the effieciency that you want) essentially provides a 'path of low resistance' for the magnetic field. This being...
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    Can Wireless Power Transmission Achieve the Speed of Light?

    In wires, you don't just have one electron. Basically, it's the old pool ball system. An electron ( or a lot of them) bang into one end of a wire. This shifts the electrons all through the wire, and some come out the other end to give you a great shock or whatever. The same thing happens in...
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    Witricity - I'd like some opinions

    Transmitting electrical power over a few feet is feasible -- I just don't believe that it's very efficient. I did find somewhere on the Witricity site, a reference to transmitting 40 watts @ 60% efficiency. They didn't go into detail about the efficiency, and I'm not going to speculate. They...
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    Witricity - I'd like some opinions

    If you google witricity, it will get you to the company. From there you can find the main theoretical guy -- His last name starts with sou I think. More googling should eventually get you to a white paper -- I've seen it, but I didn't keep it.
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    Witricity - I'd like some opinions

    witricity -- I'd like some opinions Witricity is the name of a company that hopes to sell wireless power transfer. I question their basic physics, and I'd appreciate any comments. I have no commercial interest in any of this -- it's purely an academic exercise. Also, I'm not trying to rip this...
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    Urgent BJT Current Issue Help: Understanding Passive Sign Convention

    calbraham, Not trying to rain on your parade, it was just a casual comment. If it caused any consternation, it was definitely not intentional. Have a good day, ford2go
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    Urgent BJT Current Issue Help: Understanding Passive Sign Convention

    Don't know if this is better or worse. As the last response said, the forward bias on the base causes current to flow from the emittter. (whether this is electron or hole flow is more detail than is needed. ) The 'current' mainly continues through the thin base region. A small portion of...
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