Electromagnetic radiation from most distant galaxies is redshifted when observed from Earth.
This is key evidence for the expansion of the Universe.
Which statement is correct?
Blueshift is observed when a light-emitting source is moving away from an observer.
Redshift is a decrease in the frequency of the observed electromagnetic radiation.
The expansion of the Universe means that the distance between all individual stars within our Solar System is increasing.
The Big Bang theory suggests that the Universe has always been the same size and temperature.
59 exam-style questions on CIE IGCSE Physics 6.2.3a Galaxies and the scale of the Universe. Each one has a worked solution and a mark scheme showing where the marks go.