Exam-style question
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Which of the following best describes the relationship expressed by Hubble's law?.
- A.The velocity of a galaxy is directly proportional to its distance from Earth.
- B.The velocity of a galaxy is inversely proportional to its distance from Earth.
- C.The velocity of a galaxy is independent of its distance from Earth.
- D.The velocity of a galaxy is proportional to the square of its distance from Earth.
Model answer
What a good answer should say
- The velocity of a galaxy is directly proportional to its distance from Earth.
Explanation
Why this works
Hubble's law v = H₀ × d shows a linear relationship where velocity increases as distance increases, indicating a direct proportionality.
Common mistake
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