Recent content by $id

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    Collimating light from diffraction grating

    Homework Statement Consider the following, A collimated light source impinges on a plane diffraction grating and diffracts via the well known diffraction equation. The diffracted light is then collimated by a 1 metre focal length lens (good quality one). It is experimentally verified that the...
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    A question about the flatness of the universe.

    A question about the "flatness" of the universe. I may be out of my depth here or overthinking it but... Does the fact that the universe is flat (angles in triangle add upto 180deg) mean that the complete universe has to have a edge? If it had positive curvature, then it doesn't...
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    A question about Friedmann Equations

    Hello everyone, Its been 4 years now since I posted, Last time i was asking for school homework and now I'm about to finish my physics master degree with 1 exam left in cosmology. As I'm sure you are aware, the k term in the Friedmann equation represents the curvature term k = 0, -1 & +1...
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    Error Analysis Help: Line of Best Fit with Error Bars

    I can't take any more points While i understand the box method, I was interested in a some sort of program being able to do the hard work for me lol sid
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    Error Analysis Help: Line of Best Fit with Error Bars

    Homework Statement I am trying to work out if there is an elegant way to do a line of best fit(straight) through a set of points (3) while taking into consideration their error bars? Clearly I'm looking for a piece of software that can do this. Obviously excel, etc can do a standard straight...
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    More Help yet again with Solving differential equations

    Hmm i can follow Data logic despite never have seen anything like that before, I guess now the main problem is that equation gives me the velocity. for the model i am making the data readings are distances at a given time. Hence I will most probably to integrate that beast. All i know is...
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    More Help yet again with Solving differential equations

    Hi i posted last time about solving an equation regarding air resistance being proportional to the speed This time i need it to be proportional to the speed squared I have managed to get an equation but haven't managed to solve it yet dv/dt -(k/m)v^2 = g Any ideas on how to solve...
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    Air resistance Differential Equation Help

    Unfortunately i am not aware of that method the only ones i know are auxiliary equation, separation of variables and intergrating factors Do you which one of those will work. sid
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    Air resistance Differential Equation Help

    ok fair enough, The orginal differential equation is definate correct, it was taken from a book What do you reccomend for solving that equation sid
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    Air resistance Differential Equation Help

    well g is constant as it = to 10 so isn't the equation homogenous in essence sid
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    Air resistance Differential Equation Help

    So the general solution is wrong?
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    Air resistance Differential Equation Help

    Is the actualy equation correct though? Or am i missing something sid BTW by linearise i think you mean ln(S)=LnA + LnB -RT So a plot of Kn(S) against T for some values should yeild the gradinet at -R yeah ?
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    Air resistance Differential Equation Help

    Hi guys I need help solving the following differential equation for air resistance d^2s/dt^2 + R ds/dt = g Where g = gravity I presume and R = k/m where k = resistance constant Using my limited knowledge I think that the auxiliary equation for this is Y^2+ RY = 0 Y = 0 or R...
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    What Happens to Magnetic Fields in Coils with Reversed Currents?

    (a) If the same current is passed then the flux produced (b) The magnetic poles of the solenoid is reversed. I think lol sid
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