Questions for Test #3

 

Be sure you understand all of the quizzes and homework we have had since the last test.

Be sure to look at the notes for Isaac Newton, Telescope Basics, History of Light and Spectroscopy, and the William Herschel slides

Questions about Newton

  1.  In what fundamental way are Newton's laws different from Kepler's?
  2.  State Newton's three laws of motion.
  3.  State Newton's law of universal gravity.
  4. Be able to apply Newton’s laws to examples (e.g., an object  dropped from a moving vehicle). According to Newton, what holds the earth and the planets in orbit around the sun?
  5. If you suddenly increase your speed while driving, you will feel yourself pressed back into the seat.  This is an example of one of Newton's laws. Which one? 
  6. Why is no power source needed to keep the Earth and the other planets moving in their orbits?
  7. The Earth is 1 AU from the sun.  How much weaker would the pull of gravity be if the Earth were moved out to Jupiter's orbit (5 AU from the sun)?
  8. What is the title of the book in which Isaac Newton described his theory of gravity?
  9. If the sun should suddenly disappear, how would the planets move?
  10.  Know the difference between velocity and acceleration.

Questions about Light and Telescopes

 

  1. How does a refracting telescope differ from a reflecting telescope?
  2. What feature of the telescope determines its light gathering power (LGP)?
  3. What feature of the telescope determines its resolution?
  4. How is the magnification of a telescope determined?
  5. Why are professional observatories placed on mountain tops?
  6. What is chromatic aberration?
  7. What is one disadvantage of a reflecting telescope?
  8. State the three laws of spectroscopy established by Wilhelm Bunsen and Gustav Kirchhoff.
  9. How did Plato and his school believe that light originated?
  10.  What were the earliest known lenses used by the Greeks?
  11.  What did Archimedes supposedly do with a large array of mirrors?  
  12.  Alhazen was a 10th century Persian who wrote extensively on optics and described a particular optical phenomenon later used in a common modern instrument.  What did Alhazen describe and what is it used for today?
  13.   Who was Roger Bacon, and for what two optical instruments is he known for today?
  14.  Using the wave model of light, “white light” consists of many different wavelengths.  How do our eyes distinguish between these wavelengths?  How do the longest wavelengths appear to us? How do the shortest wavelengths appear?
  15.  Where does light come from?
  16.  Who was the first person to demonstrate that white light is composed of all the colors of the rainbow?
  17.  Who discovered the first type of "invisible" light (radiation)?  How did he do it?
  18.  What is this type of invisible radiation called today?
  19.   What are two optical elements that can be used to decompose white light into its constituent colors?
  20.   Arrange the following colors in order of increasing energy: yellow, blue, green, red, orange
  21.  Looking at electromagnetic radiation as a wave phenomena, In what way do visible light , radio waves, infrared, ultraviolet, x-rays and gamma rays differ?

 

 

Questions about William Herschel

 

  1. List four major accomplishments for which William Herschel is remembered.
  2. What type of telescope did Herschel make popular and why was it more useful for his purposes than the refracting telescopes used by most astronomers of the time?
  3. What is the name of the first recognized woman astronomer since antiquity?
  4. For what astronomical work is the woman of question 8 remembered?
  5. Describe (and draw a rough sketch of) Herschel’s model of the galaxy that he developed near the end of the 18th century.  How did he arrive at this model?
  6.  What assumption did Herschel make to estimate the dimensions of the galaxy (i.e., the distance to the stars)?  What lead him to abandon this assumption later in his career?
  7. What two basic stellar properties indicate that a star might be close?
  8.  What did William Herschel hope to find by observing double stars?
  9.  What two things did William Herschel actually discover by studying double stars?
  10.  What was the definition of the word nebula as used by William Herschel?

Questions about Parallax

  1. What property of a star do we learn by measuring its parallax?
  2. Which star was the first to have its parallax measured?
  3. What was the name of the astronomer who made the first successful stellar parallax measurement?
  4. What instrument was used to make the first parallax measurement?
  5. Why is stellar parallax difficult to measure?

 

People to Know:

 

·        Edmond Halley

·        Alhazen

·        William Herschel

·        Isaac Newton

·        Christian Huygens

·        Pierre Gassendi

●    Gustav Kirchhoff

·        Giovanni Cassini

 

 

Sample Multiple Choice

 

 

____    6.   Who was leader of the team that measured the parallax of Mars by simultaneous observations in South America and Paris?

a.

Edmond Halley

b.

James Bradley

c.

William Herschel

d.

Fredrich Wilhelm Bessel

e.

Giovanni Cassini

 

 

____    7.   Who discovered that stars exhibit proper motion?

a.

Edmond Halley

b.

James Bradley

c.

William Herschel

d.

Fredrich Wilhelm Bessel

e.

Giovanni Cassini

 

 

____    8.   Whose model of the "universe" was the first based on actual observational data?

a.

Edmond Halley

b.

James Bradley

c.

William Herschel

d.

Fredrich Wilhelm Bessel

e.

Giovanni Cassini

 

 

____    9.   Which of the following was one of  William Herschel's accomplishments.

a.

Invented the diffraction grating and discovered lines in the solar spectrum.

b.

First accurate measurement of the distance to Mars and the dimensions of the solar system.

c.

First successful measurements of parallax and the speed of light

d.

Discovered a new planet and that stars have different luminosities

e.

Discovered precession and proper motion

 

 

 

 

____   12.   When studying the universe beyond the solar system, what advantage does a reflecting telescope (reflector) have over a refracting telescope (refractor)?

a.

It is much easier to make a large diameter mirror for a reflector than it is to make a large diameter lens for a refractor.

b.

The magnification can be much higher in a reflector than with a refractor

c.

Unlike the refractor, a reflector can be used with a spectroscope

d.

Unlike the refractor, a reflector can be used with a camera

e.

The aberration of starlight is not present in a reflector

 

 

____  13.