Recent content by HiggsBrozon

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    Euler Lagrange Equation Question

    Thanks for you response. I feel as if I made this problem more complicated than it should. For ∂f/∂x: ∂f/∂x = 6xy = 6x(3x4 - 2x +1) and df/dx: df/dx = ∂f/∂y * dy/dx = d/dy(3x2y + 2yy') * (12x3 - 2) = (3x2 + 2(d/dy(yy'))) * (12x3 - 2) = (3x2 + 2(y * d/dy(y') + y')) * (12x3 -...
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    Euler Lagrange Equation Question

    Homework Statement Consider the function f(y,y',x) = 2yy' + 3x2y where y(x) = 3x4 - 2x +1. Compute ∂f/∂x and df/dx. Write both solutions of the variable x only. Homework Equations Euler Equation: ∂f/∂y - d/dx * ∂f/∂y' = 0 The Attempt at a Solution Would I first just find...
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    What is the value of the dampening constant?

    After correcting my derivative I got, x' = (-Aβ - Btβ + B)e-βt Then using my initial conditions v = 0 at t = 0, 0 = (-Aβ + B)(1) → B = Aβ so, x(t) = (A+Bt)e-βt where B = Aβ and then I can use A = A/2 when t = 1s correct?
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    What is the value of the dampening constant?

    Thanks for you reply! x' = (-Aβ - Btβ + β)e-βt The velocity is 0 at t=0 so, 0 = (-Aβ + β)(1) β=0 and A = 1 Would I then go on to use t = 1 sec at A0 = A0/2 where A0 = A+βt, the initial amplitude, or is A0 equal to the value I just solved for, A = 1?
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    What is the value of the dampening constant?

    Homework Statement The shock absorber of a car has elastic constant k. When the car is empty, the design is such that the absorber is critically damped. At time t=0 the absorber is compressed by an amount A from its equilibrium position and released. a) If after 1 second the absorber...
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    Finding the ratio ω/ωo of an underdamped oscillator

    My apologies on the late reply guys. It was a late night and I ended up finishing the problem the following morning. Thanks for your help! For my equation of motion I used x(t) = Ae-βtcos(ω1t) = Ae-βmTcos(ω1mT) where ω1 = √(ω02-β2) (and yes my original formula was missing a square root.)...
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    Finding the ratio ω/ωo of an underdamped oscillator

    Homework Statement The amplitude of an underdamped oscillator decreases to 1/e of its initial value after m complete oscillations. Find an approximate value for the ratio ω/ω0.Homework Equations x''+2βx'+ω02x = 0 where β=b/2m and ω0=√(k/m) x(t) = Ae-βtcos(ω1t-δ) where ω1 has been defined as...
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