Recent content by versine

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    B How is capacitor energy the same as electrostatic potential energy?

    What do you mean separate from electrons? Aren't we bringing in ions/electrons from infinity?
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    B How is capacitor energy the same as electrostatic potential energy?

    My thought is to alternate bringing ions and electrons. Bringing the first ion would take zero work. Bringing the electron would take work. Then bringing another ion would take zero work since the the ion and electron are effectively neutral. And so on. So doesn't bringing each electron take...
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    B How is capacitor energy the same as electrostatic potential energy?

    The energy stored in a capacitor is derived by integrated the work needed to move charge dQ from one plate to another. I'm confused on how this energy is the same as electrostatic potential energy, the energy needed to assemble this configuration from infinity. In the case of capacitor energy...
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    I Chain on a slope remains still if its end points are of equal height?

    You can't break up the force into $$g\sin\theta\cos\theta$$ and $$g\sin\theta\cos\theta$$ because there is tension gradient. By Rolle's theorem there is a portion of the chain with zero slope and if you consider a mass element the tension gradient has a net vertical component. You can integrate...
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    B Why does charge oscillate in an electric dipole antenna?

    Picture: Energy source => LR Oscillator => Transformer => Transmission line => Electric dipole antenna => traveling wave Why would the charge even oscillate in the antenna as opposed to building up in the antenna? The transmission line + antenna is not a closed circuit right?
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    B Why does an inductor discharge?

    A capacitor will discharge because once a path is created there is a potential difference $V=Q/C$. But for an inductor it's $L\frac{di}{dt}$. Why would an inductor want to discharge once you connect it to a capacitor?
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    B Triboelectric charging vs charging by conduction

    Why does rubbing two objects together produce a different result than having them contact?
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    B Fluid Continuity Equation in different reference frame

    If I have fluid with area 10 and velocity 10, if the velocity increases to 20 the area will become 5. But if we switch to a reference frame moving at velocity 1 opposite this motion, then it would be 10 and 11 to 5 and 21, violating the continuity equation. What is wrong?
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    B Air escaping out of can with hole

    Because I saw the answer lol.
  10. V

    B Air escaping out of can with hole

    I think I got my first question it's because there's more area on the left side of the can.
  11. V

    B Air escaping out of can with hole

    In the first figure, air goes forward and the can goes backward. My question is why does the air exert the pressure gradient force on the can. Can I have a hint for why the can doesn't move when air is being sucked in in the second photo.
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    B Time Dilation: Traveling to a Distant Star in 4.5yr

    If there is a spaceship traveling at 0.999c, the time to reach a star 100 lyr away would be approx 100 yr (assuming no accel and decel). But on the spaceship, It would be 100 yr * sqrt(1-0.999^2) = 4.5yr. Why do we take 100 yr as the time seen on Earth and not the time on the spaceship?
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    B Newton's Rings central spot brightness

    How come when the illumination is from below, the central spot is bright, but when the illumination is from above, the central spot is dark?
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    B Potential energy in standing wave compared to traveling wave

    From hyperphysics, "The unique point in the case of the traveling wave in the string is the element of the string that is at the maximum displacement as the wave passes. That element has a zero instantaneous velocity perpendicular to the straight string configuration, and as the wave goes "over...
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    B Voltage between the positive terminal of a battery and a point in the air

    If I connect a voltmeter with the positive terminal of a battery and leave the other wire hanging in the air, it won't measure anything since it's not a closed circuit. But if there was a way to measure the voltage between those two points, what would the voltage be? Or is this a meaningless...
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