Describe the key components that power a quasar and where they are situated.
At a distance of 6.20×108 light-years6.20 \times 10^8\text{ light-years}6.20×108 light-years, a certain quasar has a measured redshift z=0.0440z = 0.0440z=0.0440. Use these data to estimate the age of the Universe in seconds. (Take 1 light-year=9.46×1015 m1\text{ light-year} = 9.46 \times 10^{15}\text{ m}1 light-year=9.46×1015 m and the speed of light c=3.00×108 m s−1c = 3.00 \times 10^8\text{ m s}^{-1}c=3.00×108 m s−1.)
A typical quasar is believed to have a power output approximately 160016001600 times that of a typical galaxy. Estimate, with reference to the inverse-square law, how much further the most distant visible quasar is likely to be compared to the most distant visible galaxy, assuming they must have the same minimum detectable brightness.
15 exam-style questions on AQA A Level Physics Cosmology (A-level only), covering Doppler effect (A-level only), Hubble's law (A-level only), Quasars (A-level only), and Detection of exoplanets (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.