This topic contains a solution. Click here to go to the answer

Author Question: How does gravitational lensing tell us about the mass of a galaxy cluster? A) The lensing ... (Read 87 times)

jon_i

  • Hero Member
  • *****
  • Posts: 549
How does gravitational lensing tell us about the mass of a galaxy cluster?
 
  A) The lensing broadens spectral lines, and we can use the broadening to weigh the cluster.
  B) Using Einstein's general theory of relativity, we can calculate the cluster's mass from the precise way in which it distorts the light of galaxies behind it.
  C) The lensing allows us to determine the orbital speeds of galaxies in the cluster, so that we can determine the mass of the cluster from the orbital velocity law.
  D) Newton's universal law of gravitation predicts how mass can distort light, so we can apply Newton's law to determine the mass of the cluster.

Question 2

What are the standard units for luminosity?
 
  A) Watts
  B) Newtons
  C) Joules
  D) kilograms
  E) Watts per second



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

Jayson

  • Sr. Member
  • ****
  • Posts: 350
Answer to Question 1

B

Answer to Question 2

A




jon_i

  • Member
  • Posts: 549
Reply 2 on: Jul 27, 2018
Excellent


Dominic

  • Member
  • Posts: 328
Reply 3 on: Yesterday
Great answer, keep it coming :)

 

Did you know?

Cyanide works by making the human body unable to use oxygen.

Did you know?

Every flu season is different, and even healthy people can get extremely sick from the flu, as well as spread it to others. The flu season can begin as early as October and last as late as May. Every person over six months of age should get an annual flu vaccine. The vaccine cannot cause you to get influenza, but in some seasons, may not be completely able to prevent you from acquiring influenza due to changes in causative viruses. The viruses in the flu shot are killed—there is no way they can give you the flu. Minor side effects include soreness, redness, or swelling where the shot was given. It is possible to develop a slight fever, and body aches, but these are simply signs that the body is responding to the vaccine and making itself ready to fight off the influenza virus should you come in contact with it.

Did you know?

Green tea is able to stop the scent of garlic or onion from causing bad breath.

Did you know?

Before a vaccine is licensed in the USA, the Food and Drug Administration (FDA) reviews it for safety and effectiveness. The CDC then reviews all studies again, as well as the American Academy of Pediatrics and the American Academy of Family Physicians. Every lot of vaccine is tested before administration to the public, and the FDA regularly inspects vaccine manufacturers' facilities.

Did you know?

Less than one of every three adults with high LDL cholesterol has the condition under control. Only 48.1% with the condition are being treated for it.

For a complete list of videos, visit our video library