Question

3.
Answer the following questions briefly:
3.1. Write the relation between the temperature and colour of a star?​

Answer 1

Answer:

The surface temperature of a star determines the color of light it emits. Blue stars are hotter than yellow stars, which are hotter than red stars. ... Remember that magnitudes decrease with increasing brightness, so if B - V is small, the star is bluer (and hotter) than if B - V is large.

Hope it helps.

Answer 2

Answer:

In practice, the magnitude of a celestial object is measured in certain wavelengths or colors using filters. This is because information about the color of stars is very useful to astronomers and gives them information about the surface temperature of a star.

The surface temperature of a star determines the color of light it emits. Blue stars are hotter than yellow stars, which are hotter than red stars. A hot star like Sirius, with a surface temperature of about 9,400 K emits more blue light than red light, so it looks brighter through a blue filter than through a red filter. The opposite is true of a cooler star such as Betelgeuse, which has a surface temperature of about 3,400 K. Betelgeuse looks brighter when viewed through a red filter than when viewed through a blue filter.