Fig. 9.1 illustrates how the radiant flux intensity $F$ from star X changes with $d^{-2}$, where $d$ is the observer’s distance from the star. Fig. 9.2 illustrates how the rate of emission $P$ of radiation from star X and the Sun varies with wavelength $\lambda$. The Sun has a surface temperature of 5770 K.
(a)[2]
State the relationship given by Wien’s displacement law.
(b)[3]
State three conclusions that can be inferred about star X from this data. The conclusions may be qualitative or quantitative. Use the space for any working.
(c)[2]
Star X is in a galaxy that is moving away from the Earth.
Suggest, with a reason, how the line for star X in Fig. 9.2 would look if the data had been obtained on the Earth.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “temperature and wavelength are inversely proportional” …