Recent content by Arm

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    Solving the Basic Mechanics Bullet Block Collision Problem

    $$ (5E-3)(v_1)=(5E-3+2)(v_2) $$ $$ \frac{1}{2} (5E-3+2)({v_2}^2)=(5E-3+2)(10)(0.2)(2) $$ $$ v_2 = 2.83 $$ $$ (5E-3)(v_1)=(5E-3+2)(2.83) $$ $$ v_1 = 1134 $$ thanks
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    Solving the Basic Mechanics Bullet Block Collision Problem

    $$ \frac{5E-3*v^2}{2} = (2 + 5E-3)(10)(0.2)(2) $$ v = 56.64 I just don't get how this is the wrong answer....it's just simple conservation of energy, right?
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    My Epic Fail at Deriving an Equation with Lagrange

    I have no idea what that means because I'm taking the equilivent of general college physics 2 right now but I'll look into it; if you have a recommended resource I'll read/watch it.
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    My Epic Fail at Deriving an Equation with Lagrange

    I see where I made the mistake sign now Ignoring variable of integration and +C for the umpteenth time has gotten me the wrong answer yet again; when will I learn my lesson? Here's the actual correct answer $$v^2 = \frac{-2k q_1 q_2}{mr} + C$$ The particle is released from rest ##x## meters...
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    My Epic Fail at Deriving an Equation with Lagrange

    I think the sign is correct
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    My Epic Fail at Deriving an Equation with Lagrange

    $$ \int v {\:} dv = \int \frac{b}{r^2} v {\:} dt $$ $$ \int v {\:} dv = \int \frac{b}{r^2} \frac{dr}{dt} {\:} dt $$ $$ \int v {\:} dv = \int \frac{b}{r^2} dr$$ $$ \frac{v^2}{2} = \frac{-b}{r}$$ $$ b = \frac{-k q_1 q_2}{m} $$ $$ \frac{v^2}{2} = \frac{(-)(-)k q_1 q_2}{mr}$$ $$ v^2 = \frac{2k q_1...
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    My Epic Fail at Deriving an Equation with Lagrange

    $$v \frac{dv}{dt} = \frac b {r^2} \frac {dr}{dt}$$ $$v {\:} dv = \frac{b}{r^2} \frac{dr}{dt}dt$$ $$\int v {\:} dv = \int \frac{b}{r^2} v {\:} dt$$ Not sure how I would take an integral with position and with velocity in it
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    My Epic Fail at Deriving an Equation with Lagrange

    fixed and fixed, thank you But I pulled the dr out of nowhere, I don't know if this is allowed
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    My Epic Fail at Deriving an Equation with Lagrange

    Here is my epic fail at trying to derive the equation using Lagrange (this was my first time trying to use lagrangian mechanics except for when I memorized the derivation for a pendulum) $$L = \frac{m \dot r^2}{2} - \frac{k q_1 q_2}{r}$$ $$\frac{\partial L}{\partial r} = \frac{k q_1 q_2}{r^2}$$...
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    Calculating Energy Dissipation for a Moving Object Using Integral Calculus

    Yeah that's what I meant, mistyped the reply
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    Calculating Energy Dissipation for a Moving Object Using Integral Calculus

    My calculus is very bad which is why I don't follow the steps where you change domains, but I ended up solving it by using ##v(x(t))## Thank you
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    Calculating Energy Dissipation for a Moving Object Using Integral Calculus

    So is ##v(x) = \dfrac{d(x(t))}{dt}##? I'm confused right now about how to represent v(x) as a derivative.
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    Calculating Energy Dissipation for a Moving Object Using Integral Calculus

    That would make it ##\int v(x)*v(t) dt##, I don't know what to do from there. (I've only done a handful of integrals before)
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