What is a light-minute?
the time for light to travel 1 million km1\text{ million km}1 million km in space
the time for light to travel from the Sun to the Earth
the distance travelled in space by light in one minute
the distance travelled by light from the Earth to the Moon
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.