Answer:
C
Explanation:
Answer A: A surface wave is a wave that travels along the surface of a medium.
Answer B, C: Electromagnetic waves are waves that have no medium to travel whereas mechanical waves need a medium for its transmission.
Answer D: The sentence in the answer D does not fit to the blank in the definition ( of the question )
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Hope this answer can help you.
Answer:
Option A applies.
A. Greater than its escape speed from the mass within the volume
Explanation:
Here it is mentioned that the spherical volume is large enough for the space to be considered as homogeneous. Also, the pressure within the volume is negligible, so that will not result into the re collapse of the Universe. Now as per our knowing, Hubble's Law relates the average speed of the particle to the distance R between the Earth and the particle. So, if the particle's speed is greater than it's escape speed from the mass within the volume, then the Universe is bound to re collapse back again. Option A applies.
Answer: IM 95%sure that the answer is B jus took the test got the answer right
Explanation:
