If we imagine that 1 in 10 million stars would eventually give rise to a civilization on an orbiting planet and assuming that there are 100 billion stars in our Milky Way galaxy, how often should a civilization randomly appear over a 5 billion year
period? A) once every 50 million years
B) once every 50,000 years
C) once every 500,000 years
D) once every 5 million years
C
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The elastic modulus of a material, except for elastomers, is proportional to the _____________of the interatomic potential.
Fill in the blank(s) with the appropriate word(s).
You are standing on a scale in an elevator and notice that your weight is lower than your normal weight. What do you conclude is occurring?
A) The elevator is accelerating upward. B) The elevator is moving at a constant velocity upward. C) The elevator is accelerating downward. D) The elevator is moving at a constant velocity downward. E) Your diet is working.
When was the first confirmed exoplanet discovered?
A) Shortly after the invention of the telescope, in the early 1600s B) In prehistoric times C) Around 350 BC, by the Ancient Greeks D) Early in the 21st century E) Near the end of the 20th century
In an isobaric process, there is no change in
A) pressure. B) temperature. C) volume. D) internal energy. E) heat.