Recent content by yuqiao

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    Study Physics in France or Italy?

    actually, i can be admitted by the top universities in these countries. do you have any comments?
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    Study Physics in France or Italy?

    It does not matter whatsoever. If I have decided, I can learn it.
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    Study Physics in France or Italy?

    I want to learn and study physics in undergraduation. In the following countries, which one do you recommend? Why? Thank you! France, Italy, Spain, Poland, Hungary
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    How Do University Systems Differ Globally?

    It seems that I am standing exactly the opposite, haha~
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    How Do University Systems Differ Globally?

    You are student under Serge Lang? That's cool!
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    Dry Cell Batteries: Chemical Reactions Involved

    Zn and MnO2, I suppose
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    What Is the Probability of No Real Roots in a Quadratic Equation?

    Homework Statement [SIZE="4"]Given an interval [0,2], randomly select two numbers a, b in it. What is the probability of the situation where the equation x^2+ax+b=0 has no real root? Homework Equations The Attempt at a Solution
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    Attraction & Force of Parallel Conductors/Loops in Magnetic Field

    for ur last question, i have to say that it is incorrect to say l=0. if u know some calculus, u will have to deal with an infinitely small arc and then add them up. another way to think about it is to consider the loop a magnetic bar placed in a magnetic field. apparently, f is not 0
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    Undergrad Internal forces on a system of particles

    when you are referring to "internal forces", your subject is the system. thus, each internal force is exerted on the system. you can think of the system a mere point, and view the internal forces as the same as the external forces. got it?