Recent content by debwaldy

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    Voltage, real reactive power question

    Would it be possible to just say that P = S and hence the voltage at the customer end will also be 33kV?
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    Voltage, real reactive power question

    we have been told to assume that all voltage values given are rms voltage values so we don't need to worry about that...
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    Voltage, real reactive power question

    Homework Statement A 33 kV single phase generator is supplying a customer a load through a cable with an impedance j2 ohms a.What voltage would the customer experience if rated current of 500 A is drawn at power factor of unity at the customer end? b. How much active and reactive power...
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    Nuclear u-235 and u-238 isotope half life question

    If i do this and substitute in t = 2 billion years i get a ratio of 0.1947, although I don't think that this is correct?
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    Nuclear u-235 and u-238 isotope half life question

    As in the equation N(t) equations? will the No be different in each case?
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    Nuclear u-235 and u-238 isotope half life question

    Homework Statement The present day value of the uranium isotopic ratio U-235/U-238 is 0.00723. The half life of U-238 is 4.51 x 10^9 and the half life of U-235 is 7.13 x 10^8 years. What was the U-235/U-238 isotopic ratio 2 billion years ago when the Oklo natural reactor was active...
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    MATLAB discretization of a 2D circular surface

    1. Hi, I am trying to model the magnetic force between two cylindrical identical sized permanent magnets. I am using the Charge/Coulombian model to do this. This assumes that all of the "magnetic charge" is on the pole ends of the magnet, i.e. the flat surfaces at the top and bottom of each...
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    Fluid hydraulics question

    Homework Statement Hi I am trying to solve this problem.I think i have the first part sorted but the second part of the question is throwing me. Given the network of pipes shown below determine the flowrate through each pipe. Use the hazen williams formula with Ch = 100. I think I have this...
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    MATLAB Plotting a 3D Gaussian in MATLAB

    Homework Statement Hi all! I'm trying to solve the following problem but I'm not too sure of a few things. Write Matlab instructions to plot a three dimensional Gaussian: A = A0exp((x^2 + y^2 + z^2)/w^2) choosing appropriate values for A0,w and range of coordinates. Homework...
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    Voltage drops - i don't understand

    Homework Statement Hi, this question is really confusing me and preventing me from completing the rest of the question. It is probably a very simple problem but i just don't understand so any help would be much appreciated. A metal- filament lamp,rated at 750W, 100V, is to be connected in...
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    Real and reactive components of current?

    Real and reactive components of current?? Homework Statement Hi there. so I am trying to solve this problem but i don't understand some of the terms used,which is obvoiusly causing some trouble. Any explanation of the terms or help would eb much appreciated. A coil having a resistance of 20...
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    Calculate RMS Voltage for 120V, 60Hz Transformer

    Homework Statement Hi, so I am just starting an rms voltage question but I'm a small bit confused. The problem states: A transformer having 90 turns on the primary and 2250 turns on the secondary is connected to a 120V, 60Hz source. Calculate a) the rms voltage and b) the peak voltage at the...
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    Internal resistance question

    and i just use the current value i have already calculated? ok i think i follow now,thanks for the help
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    Calculating Angles for Lowest First 4 Reflections of Diamond

    Homework Statement Diamond crystallises with a cubic unit cell and the lattice is face centred.Calculate the respective angles(in degrees) at which the lowest first four reflections are allowed from a polycrystalline specimen of diamond(given (wavelength)^2/4a^2 = 0.0467,where a = unit cell...
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    Internal resistance question

    i don't understand,how do you solve that equation when you dontknow what V is, do i take 1.51V as the value for V in that equation?
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