Recent content by iknowless

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    Is there actually such thing as center of mass in polar coordinates?

    I am also interested in these integrals. Some functions are just easier to work with in polar coordinates. If I remember correctly, the integral used to find area is derived my summing up areas of infinitesimal sectors of a circle. The formula for area is A=\frac{1}{2} \int f(θ)^{2} dθ
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    # of elecron/sec in a 3 bulb circuit

    Wow, how did I not see it? In formula 4 Then A_b=2A_a ! So now formula 1 can be written as E_a=4E_b There is an error in the 4th relevant equation. It should be 2emf=l(E_a+E_b)=lE_c because the closed path only travels through 1 round bulb, not 2. and the rest is algebra
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    Improper Integral Convergence for f(x)=1/(x^p)

    On the interval [0,1], which is where we are evaluating the integral, are there any points of discontinuity for values of x? If so, then the integral is improper, and you must replace that x-value with a variable, then take the limit as that variable approaches the x-value from either the...
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    # of elecron/sec in a 3 bulb circuit

    We haven't talked about resistance or Ohm's law yet. We can only use Kirchhoff's node rule, "In the steady state, the electron current entering a node in a circuit is equal to the electron current leaving the node." We can also use "i=nAuE" and the Loop Rule, where voltage around a closed...
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    Improper Integral Convergence for f(x)=1/(x^p)

    Is this your answer to part one? If so, consider that these values will make the integral diverge, not converge. Also, please show us your work. [SIZE="3"] \int_{0}^{1} x^{-p} dx = ?
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    Trying to find the radius of convergence of this complicated infinite series

    When I cancel factorials, I usually expand the factorial into maybe three or more factors, e.g. n!=n(n-1)(n-2)... and (n-1)!=(n-1)(n-2)... Then it is clear that \frac{n!}{(n-1)!}=n
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    # of elecron/sec in a 3 bulb circuit

    Homework Statement When a single round bulb of a particular kind and two batteries are connected in series, 5* 10^18 electrons pass through the bulb every second. When a single long bulb of a particular kind and two batteries are connected in series, only 2.5*10^18 electrons pass through the...
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    How Do You Calculate the Moment of Inertia for a Complex Rod Structure?

    *Light bulb* Haha, thank you! I guess it may have been easier to use the parallel axis theorem from the get-go. I_cm would then be 2(M/12*L^2) and the total mass would be 3M.
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    How Do You Calculate the Moment of Inertia for a Complex Rod Structure?

    Yes, my picture shows rotation parallel to the y-axis. In that case, isn't the moment of inertia for the rod aligned with the x-axis 1/3*M*L^2 ? Couldn't I model the other two as a particle, distance L/2 from the axis of rotation, as I suggested above? Then the moment of inertia for the...
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    How Do You Calculate the Moment of Inertia for a Complex Rod Structure?

    If so, then I = I_cm + M*D^2 = 1/3*M*L^2 + 2*M*(L/2)^2 = 5/6*M*L^2
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    How Do You Calculate the Moment of Inertia for a Complex Rod Structure?

    I would like to take this question to the end. I understand that the moment of inertia for the rod aligned with the y-axis is 1/3*M*L^2. Couldn't I model the other two rods as a particle, distance L/2 from the axis of rotation, using the formula I = M*(L/2)^2 ?
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