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  1. Amin2014 replied to the thread I 1st law of thermodynamics with chemical reaction?.

    I finally managed to sort things out in my head: Assuming the absence of kinetic and potential energy changes, the only restriction on...

    Jan 19, 2019 at 2:02 AM
  2. Dr. Courtney liked Choppy's post in the thread Admissions Maximizing the "goodness" of a recommendation letter.

    I think I understand what you're getting at, though I'm not sure I'd phrase it that way. Being aware of (and exerting some control...

    Jan 19, 2019 at 1:59 AM
  3. Delta2 liked Dr Transport's post in the thread Math Prep for Graduate E/M I.

    Jackson is a mathematical physics book disguised as an electrodynamics text.

    Jan 19, 2019 at 1:54 AM
  4. Delta2 liked luke m's post in the thread I What does coupling mean in physics?.

    I am reading Carroll’s Spacetime and Geometry, and I have seen the word “coupled” used multiple times in seemingly different ways. I...

    Jan 19, 2019 at 1:54 AM
  5. lomidrevo liked Drakkith's post in the thread I Confusion about absorption spectra - cool gasses absorb?.

    I'm betting that even in a heated gas most of the atoms/molecules are in low-energy states, allowing them to absorb incoming radiation...

    Jan 19, 2019 at 1:51 AM
  6. lomidrevo replied to the thread I Confusion about absorption spectra - cool gasses absorb?.

    As long as the discussion is about spectral lines (emission or absorption), the mechanism which is producing these lines is bound-bound...

    Jan 19, 2019 at 1:51 AM
  7. haruspex replied to the thread Calculate the change in mechanical energy during collision.

    It is still not crystal clear, but as I read post #9 the stone rebounds at 2m/s immediately after the collision. The bodies do not...

    Jan 19, 2019 at 1:45 AM
  8. aheight replied to the thread I How to confirm the function has genus 116?.

    Here is Magma code to compute the genus: > k := Rationals(); > A<z,w> := AffineSpace(k,2); > A; > C := Curve(A,(8* z-4* z^2+5* z^7-4*...

    Jan 19, 2019 at 1:35 AM
  9. Natuurfenomeen22 liked BillTre's post in the thread The Coming Coffee Crisis.

    I think a lot of coffee can be on the bitter side, but there are some that are very smooth and not bitter. They seem to be unusual and...

    Jan 19, 2019 at 1:31 AM
  10. suremarc replied to the thread I Who would win a perfect game of chess?.

    There is a threefold repetition rule in chess, whereby a draw is forced when the same position is reached thrice. Since there are a...

    Jan 19, 2019 at 1:24 AM
  11. berrytea replied to the thread Calculate the change in mechanical energy during collision.

    Blocks? There is only one block and one stone though. So, in your equation what would m2 be?

    Jan 19, 2019 at 1:23 AM
  12. Baluncore replied to the thread Jammer's interference.

    Yes you have got it. Reasoning about jamming and it's mitigation requires getting the mental concepts in order. That understanding is...

    Jan 19, 2019 at 1:17 AM
  13. Tom.G replied to the thread B Hyperloop - Orbital Space Launch.

    A bit of a math error? US vs UK Billions? 5E9 / 2.4 = 2.08E9 people; over 6 times the present USA population of 328 835 000+

    Jan 19, 2019 at 1:12 AM
  14. berrytea replied to the thread Calculate the change in mechanical energy during collision.

    Yes, it is during the collision, so from the start to the end when the spring is fully compressed.

    Jan 19, 2019 at 1:11 AM
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