If an image of a certain galaxy takes 1 minute to be exposed on film with a telescope of 1 m, objective mirror radius, how long would that same image take to be exposed with the same type of film with a telescope of 2 m, objective mirror radius? (Assume the optics on the two telescopes are such that the film in both cases covers the same angular field of view, and ignore any film reciprocity failure.)

0 votes
     4 minutes
      30 seconds
      15 seconds
      1 minute
      2 minutes
asked Sep 20, 2012 in Astronomy by anonymous
    

1 Answer

0 votes
15 seconds
answered Sep 22, 2012 by SkyStar ~Expert~ (2,855 points)



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