ANS:C - Wien's

Wien's displacement law, formulated by the German physicist Wilhelm Wien in 1893, describes the relationship between the wavelength of the peak emission and the temperature of an object that emits thermal radiation. The law states that the wavelength (λ) corresponding to the maximum intensity of radiation emitted by a black body is inversely proportional to the absolute temperature (T) of the body. Mathematically, Wien's law is expressed as: λmax​=Tb​ Where:

• λmax is the wavelength at which the radiation intensity is maximum,
• b is Wien's displacement constant (approximately equal to 2.8977729 × 10^-3 m·K),
• T is the absolute temperature of the black body in Kelvin.

In simpler terms, Wien's law tells us that as the temperature of an object increases, the peak wavelength of the radiation it emits shifts to shorter wavelengths. This means that hotter objects emit radiation with higher energy, and thus, shorter wavelengths. Conversely, cooler objects emit radiation with longer wavelengths and lower energy. Wien's displacement law is fundamental in understanding the relationship between temperature and the spectrum of thermal radiation emitted by objects, which has wide-ranging applications in fields such as astrophysics, remote sensing, and materials science.