## Astr 3000 Contemporary Astronomy Fall 2017 - Assignment 12 due Monday December 4th 2017

Help!

#### Assignment

1. Stars A and B are equally bright, but star B is 6 times further away
1. Which one is dimmer from our point of view?
2. By how much?
2. Star C has only half the brightness of star D, and is 3 times further away
1. Which one is dimmer from our point of view?
2. By how much?
3. Star E has five times the brightness of star F, and is 3 times further away
1. Which one is dimmer from our point of view?
2. By how much?
4. Star G is six times the radius of star H, and has a surface temperature twice as high
1. Which one produces the most amount of light?
2. By what factor?
5. Star K is six times the radius of star L, but has a surface temperature only half that of star L
1. Which one produces the most amount of light?
2. By what factor?
6. Compared to star M, star N is three times bigger and eight times further away. The surface temperature of start M is 4000 K, whereas the surface temperature of start N is 5000 K
1. Which one is dimmer from our point of view?
2. By how much?

Back