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Author Question: In the standard model, about when after the Big Bang did the universe become transparent to ... (Read 179 times)

KimWrice

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on: Jul 29, 2018
In the standard model, about when after the Big Bang did the universe become transparent to radiation?
 
  A)
 
  10-43 s
  B)
 
  10-35 s
  C)
 
  103 s
  D)
 
  3  105 y
  E)
 
  3  106 y

Question 2

According to the selection rule, when a photon is emitted or absorbed, transitions can only occur between state with values of  that differ by
 
  A)
 
  five units.
  B)
 
  four units.
  C)
 
  three units.
  D)
 
  two units.
  E)
 
  one unit.


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Cheesycrackers

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Reply #1 on: Jul 29, 2018
Answer to Question 1

D

Answer to Question 2

E


KimWrice

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Reply #2 on: Jul 29, 2018
Thanks


Cheesycrackers

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Reply #3 on: Jul 29, 2018
Welcome :)


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