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Author Question: Telescopes operating at this wavelength must be cooled to observe faint astronomical objects. A) ... (Read 64 times)

darbym82

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on: Jul 27, 2018
Telescopes operating at this wavelength must be cooled to observe faint astronomical objects.
 
  A) radio
  B) extreme infrared
  C) visible
  D) X-ray
  E) gamma-ray

Question 2

Ionization of hydrogen in H II regions is most visible at:
 
  A) 12,367 nm, the Paschen alpha line.
  B) 656.3 nm, Balmer alpha line for 3-2 electron transition.
  C) 21 cm in the radio region for the spin-flip of its electron.
  D) 121.3 nm, the Lyman alpha ultraviolet line for 2-1 electron transition.
  E) 473.2 nm, the blue-green emission line for 4-2 electron transition.


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adammoses97

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Reply #1 on: Jul 27, 2018
Answer to Question 1

B

Answer to Question 2

B


darbym82

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Reply 2 on: Jul 27, 2018
:D TYSM

scikid

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Reply 3 on: Yesterday
Excellent

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