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Author Question: In the standard model, about when after the Big Bang did the universe become transparent to ... (Read 180 times)

KimWrice

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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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Answer to Question 1

D

Answer to Question 2

E





 

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