Question

Why are red stars cooler than blue stars?

Answer 1

The hotter something is, the greater the frequency of radiation it emits.But since blue light is higher frequency than red light,that means that things that glow red are cooler then things that glow blue.

Answer 2

OK both stars are burning and as they burn they emit electromagnetic radiation (light) and as we move in the light spectrum red comes before blue, so the star that looks red is cooler because as the temperature decreases the colour decreases