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

Author Question: The period-luminosity relation for Cepheid variables was discovered in 1908 by A) William ... (Read 78 times)

jhjkgdfhk

  • Hero Member
  • *****
  • Posts: 569
on: Jul 27, 2018
The period-luminosity relation for Cepheid variables was discovered in 1908 by
 
  A) William Herschel.
  B) Henrietta Leavitt.
  C) Harlow Shapley.
  D) Heber Curtiss.
  E) Edwin Hubble.

Question 2

Hubble's constant is related to the age of the universe, but the precise relationship depends on the way in which the expansion rate changes with time.
 
  For a given value of Hubble's constant today (such as 24 km/s/Mly), the age of the universe is oldest if what is true? A) The expansion rate has remained nearly constant with time (a coasting universe).
  B) The expansion rate has slowed by the amount expected for a universe with the critical density (a critical universe).
  C) The expansion rate has been increasing with time (an accelerating universe).
  D) The expansion rate is slowing dramatically with time (a recollapsing universe).


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

nixon_s

  • Sr. Member
  • ****
  • Posts: 359
Reply #1 on: Jul 27, 2018
Answer to Question 1

B

Answer to Question 2

C


jhjkgdfhk

  • Member
  • Posts: 569
Reply 2 on: Jul 27, 2018
Great answer, keep it coming :)

sultana.d

  • Member
  • Posts: 320
Reply 3 on: Yesterday
Excellent

« previous next »
 

Did you know?

Nearly all drugs pass into human breast milk. How often a drug is taken influences the amount of drug that will pass into the milk. Medications taken 30 to 60 minutes before breastfeeding are likely to be at peak blood levels when the baby is nursing.

Did you know?

The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").

Did you know?

According to the FDA, adverse drug events harmed or killed approximately 1,200,000 people in the United States in the year 2015.

Did you know?

Medication errors are three times higher among children and infants than with adults.

Did you know?

Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.

Recently discovered species Tersicoccus phoenici under microscope Recently discovered species Tersicoccus phoenici under microscope
The site of Messel, Germany where Darwinius masillae was discovered. The site of Messel, Germany where Darwinius masillae was discovered.
The Taung Child, the first of the australopithecines to be discovered, is the type specimen for Aust The Taung Child, the first of the australopithecines to be discovered, is the type specimen for Aust
Anthropocene Period Anthropocene Period
Fetal Period Fetal Period
Video: Exercise and cardiac output

For a complete list of videos, visit our video library