Light from distant galaxies is red-shifted. What does this suggest about the Universe?
Answer and explanation
Correct answer: B. The Universe is expanding
- Step 1: Red shift means wavelengths are stretched.
- Step 2: This happens when sources move away, so the Universe is expanding.
Answer
The Universe is expanding.
Why not the others: The galaxies are cooling: red shift is not a temperature change. The Universe is contracting: this would cause blue shift. The galaxies are stationary: red shift shows motion away from us.
Practise more Space and Electricity.
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