« previous next »

Author Question: Why did Hubble conclude the universe must be expanding? What will be an ideal ... (Read 20 times)

casperchen82

  • Hero Member
  • *****
  • Posts: 540
on: Jul 27, 2018
Why did Hubble conclude the universe must be expanding?
 
  What will be an ideal response?

Question 2

When an electron in a hydrogen atom changes its spin from the same to the opposite direction as the proton, it
 
  A) absorbs a visible light photon.
  B) emits an X-ray photon.
  C) emits a radio wave photon.
  D) absorbs a radio wave photon.
  E) neither emits nor absorbs a photon.


mistyjohnson

  • Sr. Member
  • ****
  • Posts: 331
Reply #1 on: Jul 27, 2018
Answer to Question 1

He found the universe was not static, that the most distant galaxies showed us the highest recessional velocities and redshifts. He believed this was most easily understood by having all of spacetime itself expand, taking the galaxies with it.

Answer to Question 2

C


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

Elderly adults are at greatest risk of stroke and myocardial infarction and have the most to gain from prophylaxis. Patients ages 60 to 80 years with blood pressures above 160/90 mm Hg should benefit from antihypertensive treatment.

Did you know?

Though Candida and Aspergillus species are the most common fungal pathogens causing invasive fungal disease in the immunocompromised, infections due to previously uncommon hyaline and dematiaceous filamentous fungi are occurring more often today. Rare fungal infections, once accurately diagnosed, may require surgical debridement, immunotherapy, and newer antifungals used singly or in combination with older antifungals, on a case-by-case basis.

Did you know?

More than 34,000 trademarked medication names and more than 10,000 generic medication names are in use in the United States.

Did you know?

The first oral chemotherapy drug for colon cancer was approved by FDA in 2001.

Did you know?

According to the CDC, approximately 31.7% of the U.S. population has high low-density lipoprotein (LDL) or "bad cholesterol" levels.

True-color view of Mars seen through NASA's Hubble Space Telescope in 1999 True-color view of Mars seen through NASA's Hubble Space Telescope in 1999
Uranus's aurorae against its equatorial rings, imaged by the Hubble telescope. Unlike the auror Uranus's aurorae against its equatorial rings, imaged by the Hubble telescope. Unlike the auror
Foamy Structure of the Universe Foamy Structure of the Universe
From paintings, such as this one of Sir Walter Raleigh from 1602, some historians conclude that ... From paintings, such as this one of Sir Walter Raleigh from 1602, some historians conclude that ...
Time Line for Evolution of the Universe Time Line for Evolution of the Universe
Hubble Space telescope Hubble Space telescope
Video: Hydrogen bonds - role in the body

For a complete list of videos, visit our video library