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Home Q & A Board Science-Related Homework Help Physics Astronomy
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codytheaggie codytheaggie
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6 years ago
Why did Hubble conclude the universe must be expanding?
 
  What will be an ideal response?

Question 2

When an electron in a hydrogen atom changes its spin from the same to the opposite direction as the proton, it
 
  A) absorbs a visible light photon.
  B) emits an X-ray photon.
  C) emits a radio wave photon.
  D) absorbs a radio wave photon.
  E) neither emits nor absorbs a photon.

Question 3

What satellite revealed the most about cosmology, and why was it so effective?
 
  What will be an ideal response?

Question 4

Interstellar dust clouds are best observed at what wavelength?
 
  A) visible only
  B) radio and infrared
  C) UV and infrared
  D) radio and X-ray
  E) visible and UV
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StewartStewart
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6 years ago
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codytheaggie Author
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#2
6 years ago
Genius!!!!!!
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