Question 1
What will happen to the temperature of our sun when it becomes a red giant?
It will be cooler at that stage of its life cycle.
Question 2
What trend do you notice about star size and luminosity on the H-R diagram?
In general the larger stars are the more luminous.
Question 3
The main sequence stars follow the general trend of being more luminous when they are hotter. The other stars, though, do not always follow this trend. What factor could be contributing to this?
The giants and supergiants are luminous even though they are cool because of their great size. Remember the larger a star is, the more luminous it is. The white dwarfs are dim even though they are relatively hot because of their smaller size.
