Chapter 14, Problem 82E

(a):

Interpretation Introduction

To determine:

Explanation:

Given The telescopic photos of three stars given as,

1. The sun, which is classified as a yellow star.
2. Rigel, in the constellation Orion, which is classified as a blue-white star.
3. Betelgeuse, also in Orion, which is classified as a red star.

The temperature of the given stars is inversely proportional to the wavelength emitted by the radiation. The star whose wavelength is highest has lowest temperature among three stars and the star whose wavelength is lowest possesses highest temperature among the given stars. The order of wavelength of the colors of the given stars follows the order $(\text{iii})>(\text{i})>(\text{ii})$ . Therefore, the increasing order of temperature is just reverse to this.

(b)

Explanation:

The principle of black body radiation explains that the variation of wavelength emitted by the body with its temperature. The relation between the changes in wavelength with the temperature is given by the black body radiation concept which is written as,

${\text{λ}}_{\text{max}}\text{T}=2.898\times {10}^{-3}\text{m}\cdot \text{K}$

The order of the temperature of given stars is based on the same principle that the increase in wavelength will decrease the temperature of the star. Therefore, the principle of black body radiation is followed by the given stars.

Conclusion: The increasing order of temperature of the given stars is $(\text{iii})<(\text{i})<(\text{ii})$ .

1. The principle followed in the order of temperature of given stars is the principle of black body radiation.