Recent content by emgram769

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    Difference between static and magnetic attraction

    Most simply the forces are described by the charges and domains respectively. Static attraction (re: Coulumb's law) depends on the type of charges (being opposite or similar) and the quantity of charge. Magnetic attraction, however, depends on the "spin" of the particles and the quantity and...
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    What is the primary evidence that the Earth's outer cores is fluuid in nature?

    I have learned (currently taking an introductory Astrophysics class) that it is shown by measuring the discontinuity of seismic waves. An earthquake on one side of the Earth can be detected at various points on the other side of the Earth but on directly the opposite earthquake (as well as in a...
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    Compute Solid Angle of Cone: θ | Hi Everyone

    Try this: \int_0^{2\pi}\,\int_0^\theta\,sin\theta\,\mathrm{d}\theta\,\mathrm{d}\phi for a cone with apex angle 2theta via wikipedia
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    Moment of Inertia of a non-uniform density paraboloid

    Idisk = \int_0^{2\pi}\int_0^r r^2\rho\,r\,\mathrm{d}r\,\mathrm{d}\theta M = \int_0^V\rho\,\mathrm{d}v Change of variable to r gives different bound in the next part M = 2\pi\int_0^r\rho\,r^3\,\mathrm{d}r which I think holds true with the relationship z=r2
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    Moment of Inertia of a non-uniform density paraboloid

    Yes, it is standard notation. Sorry if that wasn't clear. I integrated with z=r^2, dz=2rdr I found c to be (5M)/(2πr^5). Final result was ()MH, can anyone verify this for me? ∫∫r^2 cr r dr dθ = c∫∫r^4 dr dθ = (c2πr^5)/5 ∫(c2πr^5)/5 2rdr = (c4πr^7)/35 M=∫ρ dv V=∫πr^2 dz = ∫πr^2...
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    Moment of Inertia of a non-uniform density paraboloid

    Homework Statement Find the moment of inertia of a paraboloid f(x,y)=x^2+y^2 whose density function is ρ(r)=cr=dm/dv. use mass M and height H to express your answer 2. The attempt at a solution I took the double integral ∫∫r^2 ρ r dr dθ to find the I of a single disk as a function of r...
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