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1. ### Reconciling Magnetism in material and the Lorentz Force equation

Thanks Tiny-Tim So if you took the spins calculated what forces are in play and what E and B fields are there, they would follow this classical Lorentz force law, or does this break down pretty quick in the face of quantum mechanics? I guess I have heard that Maxwell came up with a strange...
2. ### Reconciling Magnetism in material and the Lorentz Force equation

Hello, The Lorentz force equation, F = q (E + v x B), is a complete description of the force on bodies arising from Magnetism and Electricity, right? So somehow it must be possible to get from the magnetism that exists in materials (like in a magnet) to this equation. I don't see how the...
3. ### Area section of a sphere used for integration?

I cannot figure out why the area of a section of a sphere used for integration is: (r * dtheta) (r * sin(theta) * dphi) ? where dtheta and dphi are the differential angles that subtend the arcs, which make up the sides of the rectangle used for the differential area. I did an...
4. ### Why can you see stars (1/r or 1/r^2 dropoff of power)?

I read somewhere that people can see stars because an electromagnetic wave drops off by 1/r, therefore the power delivered by the electromagnetic wave stays strong enough to activate the receptors in your eye. I believe, this 1/r relation was realized by Maxwell when he was analyzing and...
5. ### Understanding the Cosine Wave Frequency Domain

Thanks for the patient explanations. I can't say I have intuitively grasped this yet but I am not finished playing with these new ideas provided by you all on basis, eigenfunctions, and vectors in the s plane. I just wanted to send a quick note of thanks. -xerxes73
6. ### Understanding the Cosine Wave Frequency Domain

Actually I meant, euler's inverse formula: cos x = e^ix / 2 + e^-ix / 2
7. ### Understanding the Cosine Wave Frequency Domain

So...a cosine wave when shown in the frequency domain is represented by a 1/2 magnitude vector at the positive frequency and a 1/2 magnitude vector at the negative frequency. I am surprised by this because I cannot understand why a vector of magnitude 1 at the positive frequency of the cosine...
8. ### Molecular spin alignment having macro torque effects?

Thanks! I appreciate the info. This led to some interesting reading. -Xerxes73
9. ### Molecular spin alignment having macro torque effects?

Hello, If a magnetic field aligns the electron or nuclear spins can that have a macro effect of causing torque? So for example if we had a rod and we fixed one end but allowed it to freely rotate and then aligned electron or nuclear spins would that cause the rod to rotate? Thanks, Xerxes73
10. ### Electron Precession versus Proton Precession in a Magnetometer?

Hello, Why is it that electron precession is not used in addition to proton precession in a proton precession magnetometer? It seems to me that when the frequencies are emitted as the protons precess that the electrons would do precessing at the same time and provide a secondary frequency to...