紅移與膨脹中的宇宙：練習題

Which of the following observations provides the strongest evidence that the universe is currently expanding?

Two galaxies, A and B, are observed from Earth. Galaxy A is moving away from Earth at a speed of \(v\). Galaxy B is three times further away from Earth than Galaxy A. According to the observed red shift and its relationship to distance, what is the most likely speed of Galaxy B?

An astronomer is studying the light emitted by a distant star that is moving away from the Earth. Which of the following statements correctly describes the observed light compared to the light emitted at the source?
Note: Assume the relative velocity is constant.

Cosmic Microwave Background Radiation (CMBR) is often described as the 'afterglow' of the Big Bang. Which statement best explains its origin and characteristics?

Scientists believe that the universe began with a 'big bang' approximately 14 billion years ago. Which piece of evidence is currently explained only by the Big Bang theory?

Describe how the observed wavelength and frequency of light from a distant galaxy change as a result of the Doppler effect when the galaxy moves away from Earth.

The diagram represents data collected from various distant galaxies. Use the information in the diagram and your knowledge of red shift to explain why this suggests the universe began with a Big Bang.

Explain what Cosmic Microwave Background Radiation (CMBR) is and why its presence throughout the universe supports the Big Bang model of cosmology.

An astronomer analyzes the light from two distant galaxies, Galaxy X and Galaxy Y. Both galaxies show a red shift in their spectra, but the shift for Galaxy Y is significantly larger than for Galaxy X.

Compare the motion of these two galaxies relative to Earth and explain what this observation indicates about their relative distances from our galaxy.

The Big Bang theory is supported by several key pieces of observational evidence.

a) Explain how red shift from distant galaxies supports the idea that the universe is expanding.
b) Describe Cosmic Microwave Background Radiation (CMBR) and explain why scientists consider its existence as strong evidence for the Big Bang model.