What does Wien's Law allow scientists to determine about a star?

Wien's Law describes the relationship between the temperature of a black body and the peak wavelength of radiation it emits. According to this law, as the temperature of an object increases, the peak wavelength of its emitted radiation shifts to shorter wavelengths. This relationship allows scientists to determine the temperature of a star by measuring the peak wavelength of its emitted light.

When scientists observe the light spectrum from a star, they can identify the color corresponding to this peak wavelength. For instance, a star that emits most of its energy at shorter wavelengths (blue light) is hotter than one that emits at longer wavelengths (red light). Hence, by applying Wien's Law, scientists can directly infer the temperature of the star and consequently its color, which is a fundamental aspect of understanding stellar properties.

This connection between temperature and color is why the option relating to peak wavelength and color is the correct choice, as it highlights the practical application of Wien's Law in astrophysics. Other options, while relevant in different contexts, do not directly pertain to what Wien's Law specifically helps to uncover about a star.