Is the sun hotter when its red or colder when its red?

Answer 1

Colder. White stars are hotter than red ones. For a radiating body such as the sun, the frequency of emission of light is related to its temperature, so a hotter object emits at a higher wavelength. This means blue stars are hotter than red stars. However, the question only seems to be referring to The Sun, not stars in general. The temperature of the sun is fairly constant over time, so any changes in apparent colour do not reflect a change in temperature, but merely different atmospheric conditions. Atmospheric condition, time of day, time of year and latitude all affect the apparent temperature of the sun at the Earth's surface, but these do not necessarily relate to the conditions that cause different colours, so a causal relationship cannot be assigned in this case.

Answer 2

The sun is actually hotter when it appears red, as this signifies that it is at a higher temperature. When the sun appears red, it is generally cooler in the Earth's atmosphere, giving it the appearance of being red as the light is scattered differently.