(a)[1]
Define a light-year using words.
(b)[2]
Calculate the separation between the Sun and the Earth.
(c)[3]
Use this best-fit line to find a value for the Hubble constant.
(d)[2]
Describe what redshift means.
Physics 0625 · IGCSE · Stars and the Universe
Stars and the Universe — practice question
Fig. 10.1 presents a scatter graph of the speed at which galaxies move away from the Earth against their distance from the Earth. The vertical axis is labelled speed of galaxy $10^{4}\,\text{km\,s}^{-1}$. The horizontal axis is labelled distance of galaxy from Earth $10^{20}\,\text{km}$. A best-fit line has been drawn.
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