Expanding Universe

For this week's assignment, please answer EACH of the following questions/prompts,and post them to the drop box as a single document.

1. What is a particle accelerator?
2. How do scientists use particle accelerators to study subatomic particles?
3. What particle is exchanged to generate each of the four fundamental forces?
4. What medical technologies (e.g. PET) rely on the physics of elementary particles?
5. What are the benefits of noninvasive procedures such as PET?
6. How is astronomy the oldest science?
7. How does the energy produced at the core of the Sun reach the photosphere?
8. Why won't the Sun become a supernova or black hole?
9. Why does the existence of the cosmic redshift lead to the big bang picture of the universe?
10. If a galaxy is 1,000 Mpc away, how fast is it receding from us?
11. The average temperature of the universe is 2.7 Kelvin. What is that temperature in degrees Fahrenheit?
12. The Milky Way has a radius of approximately 100,000 light years. How many miles is that? How long would it take you to travel across our galaxy if you were traveling at 50% the speed of light (be sure to show your work for full credit)?