Author Question: What form of seismic waves travel in compressions and decompressions? a. systematic waves b. ... (Read 122 times)

bobbie

  • Hero Member
  • *****
  • Posts: 592
What form of seismic waves travel in compressions and decompressions?
 
  a. systematic waves
  b. earthquake waves
  c. pressure waves
 d. shear waves
 e. gravity waves

Question 2

What observations indicate the presence of dust in the interstellar medium?
 
  What will be an ideal response?



hollysheppard095

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

c

Answer to Question 2

The dust in the ISM makes distant stars appear fainter than they would if space were
perfectly transparent. This phenomenon is called interstellar extinction, and in the neighborhood of the Sun it amounts to about 1 magnitude per thousand parsecs (pc) at visual wavelengths.

The ISM dust also affects the colors of stars. That is the reason why extinction is more severe at shorter wavelengths, which makes stars look redder than they should be. Some hot but distant O stars, for instance, actually look red and not blue. This effect is called interstellar reddening.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

Hip fractures are the most serious consequences of osteoporosis. The incidence of hip fractures increases with each decade among patients in their 60s to patients in their 90s for both women and men of all populations. Men and women older than 80 years of age show the highest incidence of hip fractures.

Did you know?

Nearly 31 million adults in America have a total cholesterol level that is more than 240 mg per dL.

Did you know?

The shortest mature adult human of whom there is independent evidence was Gul Mohammed in India. In 1990, he was measured in New Delhi and stood 22.5 inches tall.

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.

Did you know?

Historic treatments for rheumatoid arthritis have included gold salts, acupuncture, a diet consisting of apples or rhubarb, nutmeg, nettles, bee venom, bracelets made of copper, prayer, rest, tooth extractions, fasting, honey, vitamins, insulin, snow collected on Christmas, magnets, and electric convulsion therapy.

For a complete list of videos, visit our video library