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

Author Question: What is the cause of the lobes in a double-lobed radio galaxy? What will be an ideal ... (Read 37 times)

Haya94

  • Hero Member
  • *****
  • Posts: 558
What is the cause of the lobes in a double-lobed radio galaxy?
 
  What will be an ideal response?

Question 2

An astronomer records the spectrum of light coming from a distant star. Describe what information the astronomer can deduce from this stellar spectrum, and what physical principles she would apply.
 
  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

jonathanballen97

  • Sr. Member
  • ****
  • Posts: 347
Answer to Question 1

Jets from a central black hole eject large bubbles of hot gas. The hot gas glows in the radio band.

Answer to Question 2

The spectrum of light from a star will be an absorption spectrum.

The astronomer can examine the continuous radiation in the spectrum to determine the wavelength of peak intensity. Using Wien's law, this will enable the astronomer to determine the surface temperature of the star.

The absorption spectrum will contain isolated regions where the intensity of the spectrum is very low. These will appear as dark lines on a photographic spectrum. These lines are caused by the absorption of photons from electrons becoming excited to higher energy levels. By comparing the pattern of wavelengths of the dark lines with known values, the astronomer will be able to determine the chemical composition of the cool gas in the atmosphere of the star since each element has its own unique pattern of energy levels and absorption/emission lines.

The entire absorption spectrum pattern may be shifted towards the red or blue end of the spectrum. This is caused by motion of the star toward or away from the observer, and is explained by the Doppler effect.





 

Did you know?

The longest a person has survived after a heart transplant is 24 years.

Did you know?

Eating food that has been cooked with poppy seeds may cause you to fail a drug screening test, because the seeds contain enough opiate alkaloids to register as a positive.

Did you know?

Asthma occurs in one in 11 children and in one in 12 adults. African Americans and Latinos have a higher risk for developing asthma than other groups.

Did you know?

Approximately one in four people diagnosed with diabetes will develop foot problems. Of these, about one-third will require lower extremity amputation.

Did you know?

Dogs have been used in studies to detect various cancers in human subjects. They have been trained to sniff breath samples from humans that were collected by having them breathe into special tubes. These people included 55 lung cancer patients, 31 breast cancer patients, and 83 cancer-free patients. The dogs detected 54 of the 55 lung cancer patients as having cancer, detected 28 of the 31 breast cancer patients, and gave only three false-positive results (detecting cancer in people who didn't have it).

For a complete list of videos, visit our video library