Astronomy and cosmology
Astronomy and cosmology — Cambridge International A Level Physics (9702, Topic 25).
Stars and Stellar RadiationSign up
understand what is meant by a black body radiator and be able to interpret radiation curves for such a radiator · be able to use the Stefan-Boltzmann law equation L = sigma A T^4 for black body radiators · be able to use Wien's law equation lambda_max T = 2.898 x 10^-3 m K for black body radiators · be able to use the equation, intensity I = L / (4 pi d^2) where L is luminosity and d is distance from the source · understand how astronomical distances can be determined using trigonometric parallax · understand how astronomical distances can be determined using measurements of intensity received from standard candles (objects of known luminosity) · be able to sketch and interpret a simple Hertzsprung-Russell diagram that relates stellar luminosity to surface temperature · understand how to relate the Hertzsprung-Russell diagram to the life cycle of stars
Cosmology and Hubble's LawSign up
understand how the movement of a source of waves relative to an observer/detector gives rise to a shift in frequency (Doppler effect) · be able to use the equations for redshift z = lambda/lambda ≈ f/f ≈ v/c for a source of electromagnetic radiation moving relative to an observer and v = H0 d for objects at cosmological distances · understand the controversy over the age and ultimate fate of the universe associated with the value of the Hubble constant and the possible existence of dark matter.
