Recent content by TwoEG

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    Hollow cylinder magnet making contact with the circuit

    Yes, but that's not main concern for me. (Maybe I should just attached another adequate picture.) My question is, there is a magnet and a charge which moves relative to each other. In magnet's coordinate, force exerted on charge can be easily expressed via F = v x B. But how can I explain this...
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    Hollow cylinder magnet making contact with the circuit

    Homework Statement 1. Circuit moves downward while cylinder magnet is fixed. 2. Cylinder magnet moves upward while circuit is fixed. Gain emf in circuit. Homework Equations All those maxwell equations... F=v x B The Attempt at a Solution [/B] So first question is not that hard...
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    Gain of Electric Circuit: Vo/Vs and Resistance R

    Thanks for your replies! Helped me a lot :)
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    Gain of Electric Circuit: Vo/Vs and Resistance R

    Ahh... I forgot about that. But one more question. Is this mean that if I remove ground in this circuit, than the gain of circuit will become 4? I think gain of circuit must be same whether ground exists or not, since calculation using KCL and KVL on other parts of the circuit will be same.
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    Gain of Electric Circuit: Vo/Vs and Resistance R

    Homework Statement So this problem is on Introduction to Electric Circuits 9th Edition (Richard C.Dorf) This asks me to express the gain of this circuit Vo/Vs by terms of the resistance of R. Homework Equations KCL, KVL, some ideal OP AMP characteristics... The Attempt at a Solution...
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    Electric potential just after switch is opened.

    Inductor requires same current. Thanks! Now I think I can solve the equation... So does it mean that potential at A changes discontinuously from 24V to some other voltage when switch is opened? Does this instantaneous voltage change occurs in other circuits with switch?
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    Electric potential just after switch is opened.

    After switch is opened, what I know is that I should set inductor's emf like L*di/dt then apply KVL. But I feel confused when I have to set initial potential at point A after switch is opened. After applying KVL with potential B=0, I can get a exact potential at point A. So my question will be...
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    Electric potential just after switch is opened.

    Homework Statement [/B] https://postimg.org/image/6dbwajk91/ (Image inserted by moderator to make it visible in-post) In the circuit the switch is closed for several seconds, then opened. Make a graph with the abscissa time in milliseconds, showing the potential of point A with respect to...
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    Weird thinking of electric field inside a hollow cylinder.

    Thanks for cool explanation! They are canceling out each other so clearly... awesome!
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    Weird thinking of electric field inside a hollow cylinder.

    While I was studying with electric field about cylinder, I learned that for a very long cylinder, the electric field in the hollow of cylinder will be zero. http://physics.stackexchange.com/questions/156789/electric-field-of-hollow-cylinder However, I couldn't accept this intuitively, and...
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    How to gain percentage of atoms that are ionized in balloon?

    But does 'extra(or deficient) number of electrons' can really tell the 'percentage of ionized atoms'? What about distribution? If all electrons are gathered on, exaggeratedly, one point of the balloon, can I really say that balloon has same 'percentage of ionized atoms' as another balloon which...
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    How to gain percentage of atoms that are ionized in balloon?

    Homework Statement [/B] You have two inflated balloons. You rub them against your hair and hang them as shown in the figure. The length of the strings is 50 cm and the angle between them is 50°. For each balloon, what is the percentage of atoms that are ionized? Provide a rough estimate. You...
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    Why is English Considered a Difficult Language to Learn?

    English so hard :(
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