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    Hi, guys.

    +The formula of Coulomb's law:
    1) The magnitude of Coulomb's law: F= k|q1||q2|/r^2
    2) Vector F12= (kq1q2/r^2)x vector unit r

    +I don't get idea why we cannot put absolute data in the vector formula (the second formula). Why is it impossible to write:
    Vector F12= (k|q1||q2|/r^2) x vector unit r.
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    Because you'd lose the information telling you whether the force was an attraction or a repulsion.

    In your formula, every force points in the direction of r12, which is an arbitrary choice (which one is 1 and 2?), rather than depending on the signs of q1 and q2 (which it does in reality).
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