Recent content by *LouLou*

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    Conservation of Four-Momentum in Neutrino-Electron Collision

    Thanks very much, this helps with a lot of other things as well, that aren't so greatly explained in my notes. Cheers!
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    Conservation of Four-Momentum in Neutrino-Electron Collision

    Hi physics people, This is a past (3rd year university level) exam question, so I hope it's ok that I didn't post this in the homework section even if it's set out like a homework question. The Question: Suppose we are observing the collision Anti-electron-neutrino + electron ---> W-minus...
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    Classical mechanics with a mass on a light elastic string

    I think we need to add L because the question requires that we find the displacement of the mass when it catches up with the end of the string, which is L distance away from the other end of the string where the mass is attached. Since we've got the time taken for the string to slacken again...
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    Classical mechanics with a mass on a light elastic string

    So I've been working on this problem a bit more... I've been trying to find the total distance adding the distance taken for the string to become slack x(t), when t = \pi\sqrt{\frac{K}{m}} to the distance traveled by the point B x = Vt_{2} and then adding the length of the string to that giving...
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    Classical mechanics with a mass on a light elastic string

    Ok, so our answer for x(t) = Vt - \frac{V}{\omega } sin (wt). So assuming that at the instant the string looses tension the following is true Vt-x=0 we can replace Vt with x in the equation for x(t) and after some cancelations figure out that sin(wt) = 0 So wt = n\pi Assuming...
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    Classical mechanics with a mass on a light elastic string

    Oh of course thank you! So A is A = -V\sqrt{\frac{m}{K}} So the general solution becomes x(t) = Vt - V\sqrt{\frac{m}{K}} sin (\sqrt{\frac{m}{K}} t) So after I've figured out the time taken for the string to become slack, I figured that the total distance traveled until the mass...
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    Classical mechanics with a mass on a light elastic string

    So I did what you said and used m(dv/dt) = K (Vt-x) to generate the differential equation m(d^2x/dt^2) + Kx = KVt The homogeneous solution that I got is xh(t) = Asin(t(K/m)^0.5) + Bcos(t(K/m)^0.5) I found the particular solution by guessing the solution for x to be of the form x = bt^2 +...
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    Stuck on Physics Assignment: Find Force & Distance

    Can T=K log(1+au) be rearranged to give us u? u=1/a * ((10^(T/K)) -1)) If that is substituted back into the equation for force... F(T)=-(10^T/K) / Ka Does this get us anywhere?
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    Classical mechanics with a mass on a light elastic string

    Classical Mechanics Homework question Question - A light elastic string AB of natural length L and spring constant K, lies slack on a horisontal plane. A particle of mass m also at rest, is attached to end A of the string. The other end B is pulled along the plane with constant velocity V...
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