Recent content by Earthland

Homework Statement [/B] An unpolarized ruby laser operated at 0.7 μm is projected vertically into a clear sky to investigate the density of the atmosphere. A detector located 10 km from the base of the laser is used to receive the flux density scattered from the laser beam by air molecules...

You understand me correctly. Anyway, it seems I got right answers, only the order of the variables was messed up. The correct values are U_56 = 123.07692307692308 U_25 = 46.15384615384616 U_12 = 30.76923076923077 I2 = 1.5384615384615385 I1 = 4.615384615384616 I = 6.153846153846154 Thank you...

I think I reasoned as follows: First, that current trough resistors 12 and 56 is the same (current "I"), thus equations for corresponding voltages U_12/5 = U_56/20 Second, that voltage in the parallel part is equal, thus currents I1 over 25 and I2 over 2-3-4-5 satisfy the eauation...

Homework Statement I need to find voltages and currents in the following circuit, using Kirchoff laws. The purpose is not to gain knowledge in electricity, but to write a program that solves a system of equations using Gauss elimination method. I think I wrote correct program, but I also need...

Well I'll have to advance my simulations probably, once I'll figure out what could be my problem, yes :D

Hello! I'm not sure if this is the right forum for this topic, but my question is very general, not a textbook problem or something like that :) . I work in Comsol where I have imported the topography of mount St Helens and I simulate wind flow around the mountain (as laminar flow) and also...

Homework Statement I have a free Brownian particle and its coordinate is given as a function of time: And its first moment, or mean, is given as But what kind of probability density was used to calculate this first moment? Homework Equations I know that the first moment is calculated...

Thank you very much!

I didn't know where exactly should I post this kind of question :) I need to find experimental values of linear thermal expansion coefficients of copper at various temperatures (ranging 100-1500K); however, as much as I google it I only get coefficients at 20 degrees of celsius, or else there...

Both v-s produce a scalar field and thus ∇ acting on it produces a vector field, which it must be because another vector is added to it. ∇ acting on only one v means acting on vector field which would produce a tensor field. So there is some kind of relation I should use?

That's what I thought also, but I blindly followed the triple product structure provided by wikipedia. So should I just change it to ∇(v⋅v) But still, 1/2 is missing

I can't quite understand what you mean. I kept track of the order according to triple product definition, but what does it even mean to keep track on the v that ∇ is acting on? I can't just make it act on v where it isn't acting on v.

Homework Statement Need to prove that: (v⋅∇)v=(1/2)∇(v⋅v)+(∇×v)×v Homework Equations Vector triple product (a×b)×c=-(c⋅b)a+(c⋅a)b The Attempt at a Solution I know I could prove that simply by applying definitions directly to both sides. I haven't done that because that is tedious, and I...

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