Recent content by nDever

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    I Solving for the trajectory of the center of mass

    I'm working on the physics engine component of a game engine I'm building, and I need some guidance with this particular situation. Consider a square with mass M that is free to translate in the xy plane and free to rotate about any axis perpendicular to the page (Fig. 1) If a linear impulse J...
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    Number of free conduction electrons in a segment of wire

    I've written a calculator that computes the number of conduction electrons in a segment of wire with a specific gauge. For a 1 ft segment of 24awg copper wire, this is what it prints out. AWG [0 - 36]? 24 Wire length (mm) (0 - inf)? 304.8 AWG 24 radius: 0.255 mm dia: 0.511 mm area...
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    Work done under constant velocity

    Yes. Eureka. Details, details. So then, how do I interpret the notation? Do I evaluate the integral and remove the sign, flip the limits without negating the integral, ...?
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    Work done under constant velocity

    What if the displacement is from right to left? xi > xf.
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    Work done under constant velocity

    After some time of thinking, I've zeroed in a bit more on the source of my confusion, and I believe it is the misuse of the work integral. So, in the general form, the work done BY a force on a mass along a path is: $$W=\int_{C} {\mathbf F \cdot d\mathbf s}$$ If the magnitude and direction of...
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    Work done under constant velocity

    Ok then, I have this question. To compute the gravitational potential energy of a mass m2 due to the field of some other mass m1, we calculate the negative work done in bringing m2 from infinitely far away (where the field has no affect) to some other point in the field without accelerating the...
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    Work done under constant velocity

    Perfect. So then it follows that if the direction of v is reversed, then the person pushing left would be doing negative work and the person pushing right would be doing positive work?
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    Work done under constant velocity

    Depending on the answer to this question, I may have others. Consider a one-dimensional ice rink. Rightwards is taken as the +x direction. A box of mass m slides leftward on the surface with a constant velocity v. Two people go to opposite ends of the box and apply equal and opposing forces...
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    Does a Capacitor's Plate Resistance Work Like a Resistor's?

    The resistance of the capacitor plates act like all other kinds of resistance; it reduces current. However, the charges are more driven to reach the other plate than moving around in the plate. There is an electric field present when there are charges on the plates.
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    Electrons and Consequences of Conservation Laws

    Hi Guys, I was wondering; if electronic charge is conserved by Kirchoff's Current Law, then does this mean that the total number of electrons traversing any given circuit at any time is constant?
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    Understanding Back EMF and Inductors: A Closer Look at KVL and Induced Voltage

    Hi guys, I'm pretty sure this has been answered somewhere around here. So, consider a pure inductance (zero resistance) connected in series to a battery. We know that the magnitude of the induced voltage across the inductor is given by E=L\normalsize\frac{di}{dt}. According to KVL...
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    Forward voltage drop across an LED

    This is the way I was initially going about it, but I just wanted to make sure it was logical. So, using the proper calculations, as long as I use a resistor that allows about 20mA, the Vfwd will be somewhere between 1.7V and 2.6V. This is basically what the table means?
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    Understanding Momentum: Solving Simple Problems with Rocks on a Railroad Car

    You have to remember, momentum is a vector quantity, so having rocks fall down in the vertical direction doesn't change the car's velocity in the horizontal direction.
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    Forward voltage drop across an LED

    Ah, I understand. I have another related question. In the provided datasheet for the LED I want to use (LG3330), why is there a minimum and maximum Vfwd for a given constant current of 20mA? Even though diodes are non-linear, they should still give a constant forward voltage given a constant...
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    Forward voltage drop across an LED

    Did you derive this from the general diode equation?
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