This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: Why are most large telescopes reflectors, not refractors? A) Large lenses deform under their own ... (Read 48 times)

future617RT

  • Hero Member
  • *****
  • Posts: 543
on: Jul 27, 2018
Why are most large telescopes reflectors, not refractors?
 
  A) Large lenses deform under their own weight, but mirrors can be supported.
  B) Large mirrors need only one optical surface, achromats four surfaces to grind.
  C) Reflectors do not suffer from chromatic aberration like refractors do.
  D) Large, very clear lenses are harder to cast than more tolerant mirror blanks.
  E) All of the above are correct.

Question 2

How can we determine the reflectivity of an asteroid?
 
  A) by taking a photograph of it
  B) by measuring its mass and radius
  C) by comparing its brightness in visible light to its brightness in infrared light
  D) by where it is located in the asteroid belt


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

sarahccccc

  • Sr. Member
  • ****
  • Posts: 318
Reply #1 on: Jul 27, 2018
Answer to Question 1

E

Answer to Question 2

C


future617RT

  • Member
  • Posts: 543
Reply 2 on: Jul 27, 2018
YES! Correct, THANKS for helping me on my review

anyusername12131

  • Member
  • Posts: 327
Reply 3 on: Yesterday
Great answer, keep it coming :)

« previous next »
 

Did you know?

People who have myopia, or nearsightedness, are not able to see objects at a distance but only up close. It occurs when the cornea is either curved too steeply, the eye is too long, or both. This condition is progressive and worsens with time. More than 100 million people in the United States are nearsighted, but only 20% of those are born with the condition. Diet, eye exercise, drug therapy, and corrective lenses can all help manage nearsightedness.

Did you know?

In 1886, William Bates reported on the discovery of a substance produced by the adrenal gland that turned out to be epinephrine (adrenaline). In 1904, this drug was first artificially synthesized by Friedrich Stolz.

Did you know?

Illicit drug use costs the United States approximately $181 billion every year.

Did you know?

There are immediate benefits of chiropractic adjustments that are visible via magnetic resonance imaging (MRI). It shows that spinal manipulation therapy is effective in decreasing pain and increasing the gaps between the vertebrae, reducing pressure that leads to pain.

Did you know?

Urine turns bright yellow if larger than normal amounts of certain substances are consumed; one of these substances is asparagus.

Several species of squirrels have melanistic phases. In large parts of United States and Canada, the Several species of squirrels have melanistic phases. In large parts of United States and Canada, the
Nephroblastoma. A sectioned kidney reveals the presence of a very large tumor, which arose from feta Nephroblastoma. A sectioned kidney reveals the presence of a very large tumor, which arose from feta
Reflecting Telescopes Reflecting Telescopes
Flow Patterns and Large-Scale Weather: The Steering of Midlatitude Cyclones Flow Patterns and Large-Scale Weather: The Steering of Midlatitude Cyclones
Anatomy of the Large Intestine (colon) Anatomy of the Large Intestine (colon)
Video: The life cycle of protein

For a complete list of videos, visit our video library