Red-shift (physics Only) (GCSE Physics)

If a galaxy shows spectral lines shifted to longer wavelengths, and another galaxy shows the same lines shifted to shorter wavelengths, what do these observations indicate?

Hubble’s law relates a galaxy’s recessional velocity v to its distance d by v = H0 d. Which statement about H0 (Hubble constant) is correct?

Why is redshift considered stronger evidence for the Big Bang model than for a steady-state Universe?

Explain why a photon emitted at ultraviolet wavelengths long ago may now be observed as visible or infrared light due to redshift.

Why do the dark lines in the spectrum of a distant galaxy match the same pattern of lines in the Sun’s spectrum even though the lines are shifted?

A spectral absorption line has rest wavelength 500.0 nm. In a galaxy it is observed at 505.0 nm. What is the redshift z?

Which of the following best describes what a positive redshift (z > 0) of a galaxy’s light indicates?

An observed spectral line has rest 450.0 nm, observed 472.5 nm. Calculate z and state whether the galaxy is approaching or receding.

Why do astronomers compare the pattern of dark absorption lines in a star or galaxy spectrum to laboratory spectra of known elements?

Which statement about cosmic microwave background (CMB) and redshift is correct?

A spectral line with rest wavelength ?0 appears at ?obs. The redshift z = 0.2. What is ?obs / ?0 ?