Astro10/Harpell                                                                                                                   

Topics for Quiz 2

The quiz will have 20 multiple choice questions, several "fill in the blanks" about five short essay questions that may include sketches. .  If you can answer everything below, you will do well!

 

History of Astronomy :( chapter 3)

A.  Be able to summarize in one or  sentences the important contributions of each one.  Questions here are to get you focused!

Erosthatenes—how did he do what he did?

  Aristotle—what didn’t he know?

Aristarchus--what did he calculate about the earth, moon and sun? Why didn't this knowlege stick around?

Ptolemy—why did his model eventually fail? Can you sketch out his geocentric model?

Copernicus—what did he get right, and what did he have wrong?

    Brahe—his measurements of what were the best?

   Kepler—how did his work with Kepler convince him to eventually abandon his earlier ideas?

    Galileo—how did his observations disprove the geocentric model? Can you sketch what he saw regarding Venus?

   Newton—a book unto himself...how did his work rely on that of others?

Einstein—How does mass relate to energy?

Also know the approximate date when these scientists lived and worked.

In particular....

B.     Know the main differences between the Copernican (Heilo-centric)system and the Ptolemaic system (Geo-Centric)

C.     How did the Tyconic system (Tyco Brahe’s model of the solar system) differ from that of Copernicus and Ptolemy?

D.    Why was Copernicus’s model ultimately no more accurate in predicting the positions of the Planets than the Ptolemaic system?

E.     When he started working for Tyco Brahe, what model did he believe to be true for the universe (hint: think about geometric solids and musical notes)

F.     What led Kepler to abandon this model and eventually derive the correct nature of planetary orbits?

G.     What were Kepler’s three laws? 

H.    Why were Tyco Brahe’s measurements of planetary positions ultimately crucial to the work of Kepler and Newton?

I.      What telescopic observations did Galileo make that led to the ultimate rejection of the geocentric model?  Which do you think were the most important (don’t forget about the phases of Venus!)

 

Newton, Galileo and the laws of Motion (chapter 4)

J.     What were Newton’s laws of motion?

·        What is Inertia? Who did Newton get the idea from?

·        What is centripital acceleration...Who did Newton get that idea from (hint: same Italian). 

·        What does F = ma mean? Would you need to apply a force to accelerate something in empty space? 

·        Explain how Newton’s third law works...use jumping in the air, firing a cannon ball, or an astronaut pushing off the space shuttle as examples.

·        What was Newton’s Mountain?  How did it explain the relationship between free fall and orbits? What speed is something moving as it orbits

·        What is acceleration?  Be able to describe examples when you are accelerating and when you are not (don’t forget that you are accelerating when going in a circle at constant speed..Why?)

·        Understand the meaning of this sentence: “After developing Calculus, Newton was able to uses Galileo’s principles of circular motion and Inertia, and his own laws of motion and universal gravitation, to derive general forms of Kepler's laws. “   Note, you don’t have do anything with this..Just know what I’m talking about!

·        What is the law of Universal Gravitation?  How does it relate to the concept of Weight on Earth?

·        How does the force of gravity between two masses depend on the distance between them?  Why is the force on the earth due to the moon somewhat different on the near and far side of the Earth?

·        What Causes the Tides? How was Galileo wrong about it, but still on the right track?

·        What planet was discovered by applying Newton’s law of gravitation and his calculus using the orbit of a previously known planet?

·        What is Angular Momentum? 

·        The Earths spin is slowing down due to tidal friction.  How does conservation of Angular momentum explain why the Moon is moving farther away?

 

 

 Energy (chapter 4) -- you will be informed in class how much of this topic will be on the quiz!

1.       What is the definition of temperature?  

2.     What does E=mc2 mean?  Can mass be converted to energy?  Can energy be converted to mass?  How much energy could you get from a kilogram of mass?  What about a gram? Its simple math, but you will have to do it.  Note that c2 = 9 x1016 Joules/kg, or about 1017 joules/kg.   

3.     Know the meaning of different energy units: Joule, calorie, kilocalorie, Kilowatt-hour, electron volt. Know which is biggest and smallest.   How much would you have to lift to expend a joule of energy?  What about a kilowatt hour? 

4.     How much energy does it take to raise the temp of a kilogram of water by one degree?  How does the energy needed to raise the temp of the top layer of the Earth’s oceans by one degree compare with the energy released when a ten kilometer comet strikes the Earth? Is this currently happening?

5.     How does the Kinetic energy of an incoming comet of this size that wiped out the dinosaurs compare with the energy released in an H-Bomb explosion?

6.     What is the difference between energy and power?

7.     How much do you pay the power company for a kilowatt hour?  Why does this “bargain” price have to do with E = mc2

8.     What is the difference between potential energy and kinetic energy?  If you lift something, what type of energy does it gain?  What happens to the energy when you drop it?

9.     What does energy conservation mean?  Can energy be created or destroyed?  What about mass?