Recent content by PurelyPhysical

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    Graduate Conceptual Question About Magnetism

    I'm trying to get a handle on what magnetism really is. I know that charge in motion generates a magnetic field. I know that objects and particles can be permanent magnets when the magnetic fields of their elementary particles "line up." But how do stationary elementary particles have the own...
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    Velocity From Electric Potential

    This does help, thank you very much :D
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    Proof of Kinematics Equation: Eliminating Time from the Equation

    Homework Statement Eliminate t from the equation (x-xi)=vi(t)+1/2(a)t^2 using the kinematic equation v=vi+at to get v^2=vi^2+2a(x-xi) The Attempt at a Solution I wind up with (x-xi)=vi(v-vi/a) + 1/2(v^2-vi^2/a). If the first term on the right side didn't exist, I could see what the solution...
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    Vector Confusion In Applying Coulomb's Law

    I see it now. What I didn't realize is that all of the y vectors are positive because the third vector points away from the positive charge. Thank you.
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    Vector Confusion In Applying Coulomb's Law

    Why are there two distances 2 and 1? Isn't the center point equally distant from all the other points? edit: I wrote down the electric field. I see now where the constants in front of the cos are coming from. But is there a sign error for the constants in front of sin?
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    Vector Confusion In Applying Coulomb's Law

    Homework Statement http://imgur.com/48cLE6q Homework Equations Coulomb's law The Attempt at a Solution I can follow most of this problem, but I am unsure where the constants in front of the trig functions are coming from. Why is it 2cos(135), 1cos(45), 2cos(-45), etc?
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    Velocity From Electric Potential

    Thank you very much! This clears it up for me. It never occurred to me to look at ratios that way. Is there a name for what this particular concept is in math?
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    Velocity From Electric Potential

    Homework Statement http://imgur.com/UsKsaOn Homework Equations Why is the answer in joules multiplied by 2/3 and 1/2? I can follow the rest of the problem. The Attempt at a Solution [/B] I get the same solution as my teacher if I use the constants 2/3 and 1/2. I just don't understand where...
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    Undergrad Electric Field Around A Dipole?

    http://imgur.com/48cLE6q I can't follow this. Did my teacher make a mistake? Why are all the charges 2?
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    Graduate Why Are The Units of Coulombs Law What They Are?

    Thank you. That makes a lot of sense.
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    Graduate Why Are The Units of Coulombs Law What They Are?

    Why are the units of force used when applying coulombs law (N-M^2)/(C^2)? This is actually a three part question. 1. Why are the units of the permitivity constant (C^2)/(N-M^2)? 2. Why do Q1 and Q2 not contribute to the final units? Each charge is measured in coulombs, but those units don't...
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    Undergrad Why is there a space between two particles of a dipole

    Thank you, that makes sense. I was trying to imagine the particles in the dipole as protons and electrons, being the smallest positive and negative charges I could think of. I had to let go of that idea for this to make sense. Thanks again.
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    Undergrad Why is there a space between two particles of a dipole

    This is what I am referring to. How is it possible for dipoles to exist at the microscopic level, without them simply becoming a hydrogen atom?
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    What work experience is valuable for studying physics?

    I'm not the one that can benefit from this information. Sure, speaking in absolutes, there usually winds up being a contradiction, or untruth, in certain particular cases. Feel free to expound on those particular cases for Einstein's cat.
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    Undergrad Why is there a space between two particles of a dipole

    I am referring to microscopic dipoles. I know from chemistry what electron affinity is, and that Oxygen has a higher electron affinity than Hydrogen. So, the particles of the dipole would be oxygen and hydrogen respectively? But then we are considering atoms of different elements as particles of...