Author Question: Why are black holes called black? What will be an ideal ... (Read 31 times)

PhilipSeeMore

  • Hero Member
  • *****
  • Posts: 561
Why are black holes called black?
 
  What will be an ideal response?

Question 2

Explain why Copernicus' hypothesis, where the Sun was the center of the planetary system, became known as the Copernican Revolution.
 
  What will be an ideal response?



todom5090

  • Sr. Member
  • ****
  • Posts: 328
Answer to Question 1

The escape velocity of a celestial object is the speed that an object on its surface needs to escape the gravitational field. A black hole is so dense that the escape velocity is greater than the speed of light, so light cannot escape the black hole; hence, the term black.

Answer to Question 2

It became known as the Copernican Revolution because it was not just the adoption of a new idea but a total change in the way astronomers, and, in fact, all of humanity, thought about Earth and its place in the Universe. In fact, our modern use of the words revolution and revolutionary to describe philosophical, political, and social upheavals comes from the title of Copernicus's book, De Revolutionibus, which means On Revolutions.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question

PhilipSeeMore

  • Hero Member
  • *****
  • Posts: 561

todom5090

  • Sr. Member
  • ****
  • Posts: 328
Always glad to help...



 

Did you know?

Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.

Did you know?

Tobacco depletes the body of vitamins A, C, and E, which can result in any of the following: dry hair, dry skin, dry eyes, poor growth, night blindness, abscesses, insomnia, fatigue, reproductive system problems, sinusitis, pneumonia, frequent respiratory problems, skin disorders, weight loss, rickets, osteomalacia, nervousness, muscle spasms, leg cramps, extremity numbness, bone malformations, decayed teeth, difficulty in walking, irritability, restlessness, profuse sweating, increased uric acid (gout), joint damage, damaged red blood cells, destruction of nerves, infertility, miscarriage, and many types of cancer.

Did you know?

The word drug comes from the Dutch word droog (meaning "dry"). For centuries, most drugs came from dried plants, hence the name.

Did you know?

The newest statin drug, rosuvastatin, has been called a superstatin because it appears to reduce LDL cholesterol to a greater degree than the other approved statin drugs.

Did you know?

Vaccines cause herd immunity. If the majority of people in a community have been vaccinated against a disease, an unvaccinated person is less likely to get the disease since others are less likely to become sick from it and spread the disease.

For a complete list of videos, visit our video library