Recent content by dancingmonkey

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    Surface Integral of Vector fields

    Homework Statement Use Stokes' Theorem to evaluate ∫C F · dr. C is oriented counterclockwise as viewed from above. F(x, y, z) = (x + y^2) i + (y + z^2) j + (z + x^2) k C is the triangle with vertices (9, 0, 0), (0, 9, 0), and (0, 0, 9). Homework Equations Stokes' Theorem The...
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    Calculating t1: Current Through an Inductor

    Homework Statement The circuit parameters are: R = 60 Ohms, L = 5 mH, C = 40 microFarads, and e= 120 V. Initially the switch has been closed for a long time. At t=0 the switch is opened. What is t1, the first time greater than or equal to 0, that the current through the inductor is equal...
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    How to Find the Voltage Across a Capacitor in an RLC Circuit?

    My question is how do I find the voltage across a capacitor? I have an RLC circuit with a switch and battery. It only gives me the values for the battery, L, C, and R. My main question is, is there an equation or something to find the voltage across a capacitor?
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    Parametric Surfaces and their Areas

    Homework Statement Find the area of the part of the plane 3x + 5y + z = 15 that lies inside the cylinder x^2 + y^2 = 25. Homework Equations A=∫∫(√1+(dz/dx)^2+(dz/dy)^2) dA The Attempt at a Solution my bounds were r=0 to 5 and theta=0 to 2pi ∫∫√1 + (-3)^2 + (-5)^2 dA =∫∫√35 dA...
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    Finding the Centroid of a Solid

    Ah! Ok I got it now, thank you so much for helping!
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    Finding the Centroid of a Solid

    So the equation of the sphere in spherical coordinates is ρ^2=x^2+y^2+z^2. So the integral should go from p=0 to 7, right?
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    Finding the Centroid of a Solid

    So is ρ from 0 to cos(φ)? I'm still confused about this. And yes I understand that I still have to solve the integrals :)
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    Finding the Centroid of a Solid

    Homework Statement Find the volume and the centroid of the solid E that lies above the cone z=√x^2+y^2 and below the sphere x^2+y^2+z^2=49. Homework Equations The Attempt at a Solution My bounds were: \theta=0 to 2\pi \varphi=0 to \pi/4 \rho=0 to 7cos(\varphi) So my integral...
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    Triple Integrals with Cylindrical Coordinates

    Thank you so much! That was the problem. I missed the part where it said the first octant.
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    Triple Integrals with Cylindrical Coordinates

    Homework Statement Evaluate the integral, where E is the solid in the first octant that lies beneath the paraboloid z = 9 - x2 - y2. ∫∫∫(2(x^3+xy^2))dV Homework Equations x=rcosθ y=rsinθ x^2+y^2=r^2 The Attempt at a Solution θ=0 to 2π, r=0 to 3, z=0 to (9-r^2)...
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    Potential of Concentric Cylindrical Insulator and Conducting Shell

    An infinitely long solid insulating cylinder of radius a = 5.3 cm is positioned with its symmetry axis along the z-axis as shown. The cylinder is uniformly charged with a charge density ρ = 45 μC/m3. Concentric with the cylinder is a cylindrical conducting shell of inner radius b = 14.2 cm, and...
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