Recent content by Tomtom

From: 1 + (2x^-3) = (-16y^-3)(y´(x)) - (y´(x)) You cannot divide by (-16y^-3) on both sides, in order to get your next expression, because the last part of your equation -> " - y´(x) " doesn't have that factor in it. Instead, "pull out" y´(x) from the second half of the equation giving: 1 +...

You'll be happy with this answer, I believe. If you remember from regular sin and cosine rules, you have the double angle formula: sin(a+b) = sina*cosb + sinb*cosa. Well, you have equivalent functions for hyperbolic functions: sinh(a±b) = sinha*coshb ± sinhb*cosha and cosh(a±b) =...

Have I understood it correctly if I suggest that H2, N2 and O2 all rotate, but (when not considering temporary dipoles) they should not interact with photons in the microwave (nor infrared for that matter) spectrum?

Homework Statement This question is about microwave (rotational) spectroscopy. Which of the following molecules have a microwave spectrum? H2, N2, NO, N2O, CH4, CO2, OCS, H2O, Ethene, Benzene. The Attempt at a Solution According to my textbook, it appears that all molecules have a...

Hi. Something which has been bugging me a bit lately, is this: I've learned at school that from P=V*I and V=IR, we can insert the second equation in the first, and get P=I^2*R. This equation shows (probably amongst more things) that the power emitted in a wire is the square of the current, and...

I agree with citan. There's nothing difficult there at all. Derivating u(x) gives u''(x)=12 \cdot [a4] \cdot x^2+6 \cdot [a3] \cdot x (u''(x))^2=144 \cdot [a4]^2 \cdot x^4+144 \cdot [a4] \cdot [a3]x^2+36 \cdot [a3]^2 \cdot x^2 Multiply this with your E(x) (and E(x) is simplified to...

Thanks! That was what I thought, but I was unsure. How about my second and third questions?

Why does radiation of the visible spectrum move through silicon, water, ice, glass and so on? I've been wondering about this for a long time, and have been looking at various texts on the net, and the most common answer found is that it a) is because the atoms in the compound are unordered...

Is it only in the eye that colors add up to be white? I've been thinking a lot about how electromagnetic waves work. The visible light is comprised of a electromagnetic radiation in the spectrum between 380 and 750 nm. Now, as far as I understand, if you "mix" all of these waves together...

I'm very curious about that last part Spetsop: Who has been measuring the dark matter, and where can I find a conclusion reached for the amount of it in the universe?

Pardon me for reviving this thread, but I've just read Feynman's book myself, and wanted to try this kind of differential work. Saltydog: I was very happy to see that you provided an example for us to try. However, I'm finding that solving your second example was easier the regular way (first...

Ah, this is grand! JesseM, that was brilliantly explained, thank you very much! I'm really grasping this now! :)

This response is the same as my edit above: After thinking a bit about this, I realize that I'm probably going to get a couple of answers stating "massed objects can't reach the speed of light", it would take infinite energy. Well, that's fine with me, those who have a problem with that aspect...

Say you launch a rocket from earth, towards planet Zulu. The rocket travels at approximately c, relative to an observer on Zulu. Now, the rocket is pretty large, and fires a rocket from this rocket - a tiny rocket (so there's only a miniscule change in momentum). This rocket travels at a...

Very interesting MeJennifer! Great to find that there exists understandable research on the subject! My mathematics (and physics) are only slightly above A-level-equivalent, so I didn't understand most of the math, but the conclusion was "readable". =)