Question

19 which of the following supports the theory that the universe is expanding? a redshift of light from distant galaxies b blueshift of light from distant galaxies c nuclear fusion occurring in the sun d radioactive decay occurring in the sun show hint

Explanation:

To determine which option supports the theory of the expanding universe, we analyze each choice:

• Option A: Redshift occurs when light from distant galaxies is stretched (wavelength increases) as galaxies move away from us. This observation (Hubble's law) is key evidence for the universe's expansion.
• Option B: Blueshift indicates objects moving toward us, which would suggest contraction, not expansion, so it's incorrect.
• Option C: Nuclear fusion in the Sun relates to energy production in stars, not cosmic expansion.
• Option D: Radioactive decay in the Sun is unrelated to the universe's expansion.

Thus, redshift of light from distant galaxies supports the expanding universe theory.

Answer:

A. Redshift of light from distant galaxies