Recent content by armolinasf

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    Expressing Spherical coordinates in terms of cylindrical

    Homework Statement I'm trying to express spherical coordinates in terms of cylindrical and vice versa. I would appreciate it if someone could give me some feedback on my attempt at a solution. Thanks for the help! The Attempt at a Solution Spherical(cylindrical) r=(ρ^2+z^2)^(1/2)...
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    Gauss' Law for nonconducting sphere

    Gauss' law relates flux and charge and flux measures the electric field over a given area. Symmetry arguments are used to define the area through which the electric field "flows" correct? so if there is not enough symmetry to define a solvable integral then it dosen't allow you to define flux...
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    Gauss' Law for nonconducting sphere

    I know that there is a superposition of forces involved but I'm having difficulty seeing exactly how/where it applies
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    Gauss' Law for nonconducting sphere

    So for my argument to work the outer charge distribution has to be symmetrical? Why is that exactly? But taking that into consideration I can see that it is symmetrical with respect to the y and z axes which would explain why the electric field has an x component only.
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    Gauss' Law for nonconducting sphere

    Homework Statement There is a nonconducting solid sphere with uniform charge density rho and radius R=15 but it has a smaller hollow spherical cavity of radius a = 5, it is not centered: the distance between the center of the larger sphere is a distance b = 6 I'm trying to find the...
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    Landing a 747 with only friction

    Homework Statement I had this problem floating around in my head and when I worked it out I was a little surprised. A 747 is coming in for a landing and the only force opposing its motion is the force of friction between the ground and its tires how much runway is needed for the plane to come...
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    Line integral, Error in my textbook?.

    Homework Statement Evaluate the line integral: int(ydx+xdy) where the path C is y=sinx from (0,0) to (pi/2,0) Homework Equations The Attempt at a Solution (pi/2,0) is not a solution to y=sinx. I could use the fundamental theorem but for my potential function I get F(x,y)=xy...
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    Thermodynamics: Efficiency for Stirling engine

    why is that? isn't nRThln(r) the work done from 1-2?
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    Thermodynamics: Efficiency for Stirling engine

    Yes, but the heat flow occurring in 2-3 is an out flow so it wouldn't be included in the efficiency calculation which is based on only on the heat input, right?
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    Thermodynamics: Efficiency for Stirling engine

    Homework Statement I'm trying to find an expression for the efficiency of a stirling engine operating with an ideal diatomic gas, and cycling through a volume V and a multiple of its compression ratio, r, Vr. Homework Equations processes: 1-2 isothermal expansion 2-3 isochoric...
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    Finding specific heat of an object graphically

    Homework Statement Samples A and B are at different initial temperatures when they are placed in a thermally isolated container and allowed to come to thermal equilibrium. Figure a gives their temperatures T versus time t. Sample A has a mass of 5.2 kg; sample B has a mass of 1.6 kg. Figure...
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    Thermo: Newtons law of cooling for radiation

    Homework Statement A cube of copper of mass 4 kg and initial temperature of 110 oC is set to radiatively cool in an environment of 100 oC. (Note: copper has an emissivity of about 0.05. Also, neglect conduction and convection as cooling agents in this problem.) The surface area of the...
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    How Do You Calculate the Combined Phase Angle Shift of Multiple Waves?

    Homework Statement If I have three different waves each with difference amplitude and phase angle how would i find the combined phase angle shift? wave 1: A=5 phi=0 wave 2: A=5 phi=pi/4 wave 3: A=9 phi=pi/2 Homework Equations phi'=arctan(a2sin(phi)/(a1+a2cos(phi)), where phi in...
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    Calculating Phase Angle and Amplitude for a Sinusoidal Wave on a String

    for c I would just solve t for -A correct, omega would be negative since the wave is moving rightward? arcsin(-1)/(-2pi*230)=t=.0011 Does this make sense?
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    Basic Harmonic Frequencies Question

    Homework Statement A string is stretched between fixed supports separated by 82.0 m. It is observed to have resonant frequencies of 334.000 and 389.667 Hz, and no other resonant frequencies between these two. A)What is the lowest resonant frequency of the string? B)What is the wave...
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