20230503

pset 3

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    • Be careful because you can’t do the proof without this.
  • It seems important to have the idea that you can do a ^1/2 binomial approximation when looking at roots.

    • It’s done everywhere.

E&M

  • When differentiating , replace it with and calculate.
    • It becomes .
  • It’s quite important not to lose the direction information of vectors in the field. (blu3mo)(blu3mo)(blu3mo)
  • Why prac exam 2e?

Things to memorize

  • Beta transformation.
  • Derivation of acc?
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    • In addition,
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    • image
    • Thus, the acceleration in the x direction, as

    • seen in the primed frame, is reduced compared to that in the rest frame by three powers of γ, two from time

    • dilation and one from Lorentz contraction. However, the perpendicular components of the acceleration are only

    • reduced by two powers of γ– the ones due to the time dilation.

      • Genius (blu3mo) imageimage

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  • Not values but formulas

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Integrate energy density over the entire space

  • C=Q/|Φ|

  • J=i/A

  • R=L/σ_c

  • C=ε_0A/d

  • E = λ/2πϵ_0r

  • By default, timelike

Check with OH

  • Understanding causality
  • p406 x direction