Which statement about redshift and the expansion of the Universe is correct?
Redshift describes an increase in the frequency of light emitted by receding galaxies.
The redshift observed in light from distant galaxies provides evidence that the Universe is expanding.
Blue-shift is observed when a galaxy is moving away from the observer.
There are only about one million galaxies in the observable Universe.
104 exam-style questions on CIE IGCSE Physics 6.2 Stars and the Universe, covering 6.2.1 The Sun as a star, 6.2.2a Galaxies and astronomical distances, 6.2.2b The life cycle of a star, 6.2.3a Galaxies and the scale of the Universe, 6.2.3b Redshift, 6.2.3c The Big Bang Theory and cosmic microwave background radiation, and 6.2.3d The Hubble constant and the age of the Universe. Each one has a worked solution and a mark scheme showing where the marks go.