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Home Q & A Board Science-Related Homework Help Physics Astronomy
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skyleton skyleton
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6 years ago
The Hubble time is
 
  a. the time it takes a galaxy moving at 1000 km/s to move 1 Mpc.
  b. the time it takes the galaxy to double its size.
  c. the time since recombination occurred.
  d. the time remaining before the Universe stops expanding and begins to contract.
  e. an estimate of the age of the Universe based on the Hubble constant.

Question 2

A Type II supernova produces a planetary nebula.
 
  a. True
  b. False
  Indicate whether the statement is true or false

Question 3

During the first moments of the big bang when elements could be created, nuclear fusion reactions made few heavy elements because
 
  a. all heavy nuclei are unstable.
  b. no stable nuclei exist with masses of 5 or 8 hydrogen masses.
  c. the helium nucleus is unstable.
  d. the temperature and density were too low.
  e. no nuclei heavier than helium could form since there weren't any electrons formed.

Question 4

Synchrotron radiation occurs when high-speed electrons move through a magnetic field.
 
  a. True
  b. False
  Indicate whether the statement is true or false
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destiny_remydestiny_remy
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6 years ago
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skyleton Author
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#2
6 years ago
TY
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6 years ago
My pleasure
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