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

Author Question: What is the Hubble constant essentially a measure of? a. the number of galaxies in the universe ... (Read 72 times)

ec501234

  • Hero Member
  • *****
  • Posts: 573
on: Jul 27, 2018
What is the Hubble constant essentially a measure of?
 
  a. the number of galaxies in the universe
  b. the expansion of the universe
  c. the age of the Milky Way galaxy
  d. the amount of dark matter in an average galaxy

Question 2

Why are interstellar absorption lines so narrow compared to the width of lines which originate in the photospheres of stars?
 
  What will be an ideal response?


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

juiceman1987

  • Sr. Member
  • ****
  • Posts: 316
Reply #1 on: Jul 27, 2018
Answer to Question 1

b

Answer to Question 2

Much of the interstellar gas is cold, and its density is very low. Because atoms in the ISM move slowly and collide only rarely, interstellar absorption lines are extremely narrow.


ec501234

  • Member
  • Posts: 573
Reply 2 on: Jul 27, 2018
Gracias!

Perkypinki

  • Member
  • Posts: 339
Reply 3 on: Yesterday
Wow, this really help

« previous next »
 

Did you know?

To combat osteoporosis, changes in lifestyle and diet are recommended. At-risk patients should include 1,200 to 1,500 mg of calcium daily either via dietary means or with supplements.

Did you know?

More than one-third of adult Americans are obese. Diseases that kill the largest number of people annually, such as heart disease, cancer, diabetes, stroke, and hypertension, can be attributed to diet.

Did you know?

Many medications that are used to treat infertility are injected subcutaneously. This is easy to do using the anterior abdomen as the site of injection but avoiding the area directly around the belly button.

Did you know?

Interferon was scarce and expensive until 1980, when the interferon gene was inserted into bacteria using recombinant DNA technology, allowing for mass cultivation and purification from bacterial cultures.

Did you know?

Patients who cannot swallow may receive nutrition via a parenteral route—usually, a catheter is inserted through the chest into a large vein going into the heart.

Scale used to measure pupil size in millimeters. Scale used to measure pupil size in millimeters.
When the number of miles traveled is considered, drivers under 25 years of age and those over 70 are ... When the number of miles traveled is considered, drivers under 25 years of age and those over 70 are ...
Calculate the number of sodium ions in 0.375moles of Na2CO3.10H20 Calculate the number of sodium ions in 0.375moles of Na2CO3.10H20
Drawings depicting mitosis in an animal cell with a diploid number of 4 Drawings depicting mitosis in an animal cell with a diploid number of 4
A ship is being pulled through a harbor at constant velocity by two tugboats as shown in the ... A ship is being pulled through a harbor at constant velocity by two tugboats as shown in the ...
Comparison number Grade 1 math Comparison number Grade 1 math
Video: Pressure volume relationships - Normal inspiration and expiration

For a complete list of videos, visit our video library