Multiple Choice
What atomic transition occurs in the atoms of hydrogen gas in the spiral arms of the Milky Way Galaxy to produce the 21-cm radio emission?
A) transition from n = 2 level to n = 1 level in atomic hydrogen
B) change in rotation of the molecule H2 about an axis perpendicular to the molecular axis
C) change in the vibrational state of the H atoms in the H2 molecule
D) inversion of the electron spin relative to the proton spin, from parallel to antiparallel
Correct Answer:
Verified
Correct Answer:
Verified
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