Recent content by SumDood_

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    B Should I be treating the data I have as a Population or Sample?

    Well, yes. That is what I am trying to find out. How does one determine whether any value of central tendency is appropriate or not for a given sample?
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    B Should I be treating the data I have as a Population or Sample?

    Then, does that mean that the mode becomes a relevant central tendency measure? I would say it isn't because it does not provide much information about the sample. If we already know the probability of each sample being drawn is equal, then what benefit does the mode value provide?
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    B Should I be treating the data I have as a Population or Sample?

    When taking a sample from a uniform distribution, every real number within 0 and 1 has equal probability of being drawn. I would think that there would be no mode, as no 2 values would be the same.
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    B Should I be treating the data I have as a Population or Sample?

    A study on strength properties of high-performance concrete obtained by using super-plasticizers and certain binders recorded the following data on flexural strength (in mega-pascals, MPa) from 28 tests: 6.1, 5.6, 7.1, 7.3, 6.6, 8.0, 6.8, 6.6, 7.6, 6.8, 6.7, 6.6, 6.8, 7.6, 9.3, 8.2, 8.7, 7.7...
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    Engineering Intro to Power Systems: AC RLC circuit voltage calculations

    $$\left| \frac{V_R}{V_S} \right| ^2 = \frac{R^2}{R^2 - 2R^2 \omega^2 L C + R^2 \omega^4 L^2 C^2 + \omega^2 L^2 }$$ Let's try one more time: \begin{align*} \frac{d}{dC}\left| \frac{V_R}{V_S} \right| ^2 &= \frac{d}{dC}\left(\frac{R^2}{R^2 - 2R^2 \omega^2 L C + R^2 \omega^4 L^2 C^2 + \omega^2 L^2...
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    Engineering Intro to Power Systems: AC RLC circuit voltage calculations

    @The Electrician I tried this: \begin{align*} V_R &= V_S \cdot \frac{R}{R + \left( j \omega L \right) \left(j \omega R C + 1 \right)} \\ \\ V_R &= R\cdot V_S \cdot \left( R-\omega^2RLC+j\omega L\right)^{-1} \\ \\ \frac {dV_R} {dC} &= -R\cdot V_S \cdot \left( R-\omega^2RLC+j\omega L\right)^{-2}...
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    Engineering Intro to Power Systems: AC RLC circuit voltage calculations

    You guy's help is extremely appreciated! \begin{align*} 1 &= \frac{R^2}{\left( R - \omega^2 LRC\right)^2 + \left(\omega L\right)^2} \\ \\ R^2 &= \left(R - \omega^2 LRC\right)^2 + \left(\omega L\right)^2 \\ \\ R^2 &= R^{2}-2\omega^2R^2LC+\omega^4R^2L^2C^2 + \left(\omega L\right)^2 \\ \\ 0 &=...
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    Engineering Intro to Power Systems: AC RLC circuit voltage calculations

    @The Electrician Tried again: \begin{align*} \frac{R}{R-(j\omega ^{2}RLC + j\omega L)} \cdot \frac{R-\omega ^{2}RLC-j\omega L}{R-\omega ^{2}RLC-j\omega L} &= \frac{R^{2}-\omega ^{2}R^{2}LC - j\omega RL}{(R-\omega ^{2}RLC)^{2}+(\omega L)^{2}} \\ \\ &=\frac{R^{2}-\omega ^{2}R^{2}LC}{(R-\omega...
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    Engineering Intro to Power Systems: AC RLC circuit voltage calculations

    @The Electrician So I tried rationalization, but ended up with an expression that has j in the denominator: \begin{align*} \frac{R}{R+(j\omega L)(j\omega RC+1)} \cdot \frac{R-(j\omega L)(j\omega RC+1)}{R-(j\omega L)(j\omega RC+1)} &= \frac{R^{2}-R(-\omega ^{2}RLC + j\omega L)}{R^{2}-[(-\omega...
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    Engineering Intro to Power Systems: AC RLC circuit voltage calculations

    $$1=\left| \frac{R}{R+(j\omega L)(j\omega RC+1)}\right|$$ I think I get it: $$(j\omega L)(j\omega RC+1) = -2R$$ OR $$(j\omega L)(j\omega RC+1) = 0$$ \begin{align*} (j\omega L)(j\omega RC+1) &= -2R \\ -\omega ^{2}RLC + j\omega L &= -2R \\ -\omega ^{2}RLC &= -2R - j\omega L \\ C &= \frac{-2R -...
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    Engineering Intro to Power Systems: AC RLC circuit voltage calculations

    ##V_{S} = 120V ## ##f = 60Hz## ##L = 20mH## ##R = 10\Omega ## (a) Assume the capacitance is omitted. What is the resistor voltage? ##X_{L} = j\omega L = j2.4\pi## ##V_{R} = Vs\cdot \frac{R}{R+X_{L}} = 76.5067-j57.6847## ##V_{L} = Vs\cdot \frac{X_{L}}{R+X_{L}} = 43.493+j57.6847## (b) What...
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    Engineering Intro to Power Systems: Calculating Power

    It seems that everyone is finding this question to be weird. So, I'll post the solution that is at the end of the book: ##P = \frac{1}{2}VIcos(\psi)## ##Q = \frac{1}{2}VIsin(\psi)## Instantaneous power ##p=2Pcos^{2}(\omega t)+Qsin(2\omega t)##
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    Engineering Intro to Power Systems: Calculating Power

    You are right that this kind of circuit won't exist in the real world, but the question I've described is as stated in the book.
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    Engineering Intro to Power Systems: Calculating Power

    What I have provided is what is mentioned in the question. Let's assume that the current source is delivering power.
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    Engineering Intro to Power Systems: Calculating Power

    Help me understand what I am missing. So this is the circuit: Given: ##V_{RMS} = 120V## ##I_{RMS}= 10A## ##v=Re \{Ve^{jwt}\}## ##i=Re \{Ie^{j(wt-\psi)}\}## (a) Calculate and sketch real and reactive power P and Q as a function of the angle ψ (b) Calculate and sketch the instantaneous power...
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