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

Author Question: Briefly explain why radiation was trapped for 300,000 years during the era of nuclei, and why the ... (Read 20 times)

anjilletteb

  • Hero Member
  • *****
  • Posts: 569
Briefly explain why radiation was trapped for 300,000 years during the era of nuclei, and why the cosmic background radiation broke free at the end of this era.
 
  What will be an ideal response?

Question 2

The most likely way we could terraform Mars would involve
 
  A) adding greenhouse gases to the atmosphere
  B) moving the planet closer to the Sun
  C) restarting Martian volcanoes
  D) firing projectiles into the polar caps



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

AaaA

  • Sr. Member
  • ****
  • Posts: 339
Answer to Question 1

During the era of nuclei, the universe consisted of a hot plasma of hydrogen nuclei, helium nuclei, and free electrons. Throughout this era, photons bounced rapidly from one electron to the next, just as they do deep inside the Sun today, never managing to travel far between collisions. If a nucleus managed to capture an electron to form a neutral atom, one of the photons quickly ionized it. This era came to an end when the expanding universe had cooled down to about 3,000 K. At this temperature, the hydrogen and helium nuclei were able to capture electrons and form stable, neutral atoms for the first time. With electrons bound into atoms, the photons began to stream freely across the universe.

Answer to Question 2

A





 

Did you know?

Stroke kills people from all ethnic backgrounds, but the people at highest risk for fatal strokes are: black men, black women, Asian men, white men, and white women.

Did you know?

In the United States, congenital cytomegalovirus causes one child to become disabled almost every hour. CMV is the leading preventable viral cause of development disability in newborns. These disabilities include hearing or vision loss, and cerebral palsy.

Did you know?

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

Did you know?

Fatal fungal infections may be able to resist newer antifungal drugs. Globally, fungal infections are often fatal due to the lack of access to multiple antifungals, which may be required to be utilized in combination. Single antifungals may not be enough to stop a fungal infection from causing the death of a patient.

Did you know?

Drug abusers experience the following scenario: The pleasure given by their drug (or drugs) of choice is so strong that it is difficult to eradicate even after years of staying away from the substances involved. Certain triggers may cause a drug abuser to relapse. Research shows that long-term drug abuse results in significant changes in brain function that persist long after an individual stops using drugs. It is most important to realize that the same is true of not just illegal substances but alcohol and tobacco as well.

For a complete list of videos, visit our video library