This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: How did Harlow Shapley use the period-luminosity relationship of RR Lyrae variables to determine the ... (Read 90 times)

luminitza

  • Hero Member
  • *****
  • Posts: 555
on: Jul 27, 2018
How did Harlow Shapley use the period-luminosity relationship of RR Lyrae variables to determine the size of the Milky Way galaxy?
 
  a. He determined the proper motion of globular clusters in the outer disk of the galaxy.
  b. He found the distances to individual variables free floating in the halo.
  c. He found the distances to open clusters found throughout the disk of the galaxy.
  d. He found the distances to globular clusters distributed about the center of the galaxy.

Question 2

What causes the outward gas pressure that balances the inward pull of gravity in a main-sequence star?
 
  a. the rapid outward flow of gas
  b. the rapid inward flow of the gas
  c. the high temperature of the gas
  d. the high density of the gas
  e. the high temperature and the high density of the gas


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

aruss1303

  • Sr. Member
  • ****
  • Posts: 314
Reply #1 on: Jul 27, 2018
Answer to Question 1

d

Answer to Question 2

e


luminitza

  • Hero Member
  • *****
  • Posts: 555
Reply #2 on: Jul 27, 2018
Thank you!


aruss1303

  • Sr. Member
  • ****
  • Posts: 314
Reply #3 on: Jul 27, 2018
Always glad to help...


« previous next »
 

Did you know?

The human body produces and destroys 15 million blood cells every second.

Did you know?

Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.

Did you know?

Though newer “smart” infusion pumps are increasingly becoming more sophisticated, they cannot prevent all programming and administration errors. Health care professionals that use smart infusion pumps must still practice the rights of medication administration and have other professionals double-check all high-risk infusions.

Did you know?

Of the estimated 2 million heroin users in the United States, 600,000–800,000 are considered hardcore addicts. Heroin addiction is considered to be one of the hardest addictions to recover from.

Did you know?

More than 30% of American adults, and about 12% of children utilize health care approaches that were developed outside of conventional medicine.

Approach used to determine the evolutionary relationships among many animal species using molecular Approach used to determine the evolutionary relationships among many animal species using molecular
The vagina, sagittal section showing the location of the vagina and its relationship to the cervix, The vagina, sagittal section showing the location of the vagina and its relationship to the cervix,
Relationship of Victims and Rapists Relationship of Victims and Rapists
Embryonic Period Embryonic Period
The relationship between allelic frequency and genotypic frequency in a population that is in Hardy- The relationship between allelic frequency and genotypic frequency in a population that is in Hardy-
Relationship between birth weight and mortality in humans Relationship between birth weight and mortality in humans
Video: The Nerve Impulse

For a complete list of videos, visit our video library