Recent content by Geromy

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    Differential Difficulties in an RL Circuit Problem

    The back Emf opposes the direction of current flow, so it's negative until the current starts switching directions, is my understanding
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    Differential Difficulties in an RL Circuit Problem

    V = R(dQ/dt) - L(dI/dt) The problem is I don't know the equation describing Q - I've found a candidate, but I'm not terribly confident about it.
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    Differential Difficulties in an RL Circuit Problem

    Ah! Yes, okay - I think that's already been essentially completed. The circuit is a single loop in series, so V = IR + Emf, like I put above.
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    Differential Difficulties in an RL Circuit Problem

    I don't know anything about KCL... After doing a little research, though, it looks like maybe Q(t) = L*V(1-e^(tR/L)): if this is true, then it's just a matter of derivatives. I'm not sure it's right, though (I cobbled it together from Wikipedia and Hyperphysics) - would knowing the KCL help...
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    Differential Difficulties in an RL Circuit Problem

    Okay! But I'm kind of lost there, too - what information do I need to construct the differential equation?
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    Differential Difficulties in an RL Circuit Problem

    Homework Statement An inductor with L = 50 mH is in series with a resistor of R = 180 ohms. At t = 0, a potential difference of 45 V is suddenly applied across the series circuit. At what rate is the current increasing after 1.2 milliseconds? Homework Equations V = IR + Emf Emf =...
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    Two Charged Masses Suspended From Strings

    Haha, so, I figured it out! I thought I would post here in case anyone wants an explanation. Consider the forces acting on a single one of the charged masses: the force due to the charges is kq2/x2 - x is the radius between the two charges, since it's the distance they're separated by. The...
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    Two Charged Masses Suspended From Strings

    Homework Statement Two similar tiny balls of mass m are hung from silk threads of length L and carry equal charges q. The angle formed by the two strings is bisected by an imaginary line, forming angle θ. Assume that θ is so small that tan θ can be replaced by its approximate equal, sin θ...