Study Questions - Idea 2 (Chapter 3) B. Ellman Section 005

 

1. What is a deterministic system and what does this concept have to do with this Idea?

2. What is speed?

3. What is velocity and how is it different than speed? Give an example of two things with the same speed but different velocities.

4. What does a distance vs. time graph look like for a constant velocity object?

5. What does a distance vs. time graph look like for a constant velocity object moving twice as fast as the one in question 4?

6. We learned that velocity is relative. What does this mean? Give an example that explains it.

7. What did Aristotle think made object move in projectile motion?

8. What does Newton have to say about the motion of objects when no forces are applied?

9. What does Newton have to say about the motion of objects when forces are applied (the second law).

10. Why were inclined planes important in the story of motion?

11. What is acceleration? Give an example of acceleration that does not involve a change in speed.

12. What quantities determine how big an acceleration is caused by a force?

13. What is Newton's third law? What does it have to do with firing a rocket engine in class?

14. What is the mass of an object in deep space compared to its mass on Earth? What is the weight of an object in deep space compared to its weight on Earth?

15. Which falls faster in vacuum: a feather or Marlon Brando?

16. Try, as best you can, to explain the answer of question 15.

17. If I drop an object in a liquid (even in air), its motion is different than if I drop it in vacuum. How does it differ and what does that have to do with Aristotle?

18. Explain Galileo's theory (which is correct) of projectile motion.

19. In class I walked at uniform speed and dropped something, which always hit the ground right at my feet. This can be explained by combining a Newton law with something from Galileo - how?

20. Explain as best you can, in words, Newton's law of gravity. How does the force vary with masses and distance?

21. Here’s a potentially tough one - explain how Newton's third law (equal strength opposite forces) is contained in his law of gravity.

22. Why would you weigh much less on the moon than on Earth? (Give a better answer than "because gravity is weaker on the moon - why is it weaker?)

22. Orbits: If I have a stationary object above the Earth and let go it will simply fall into the Earth. If, however, I give it a good push, it will orbit. Why??? Think back to the in-class simulations and discussion.

23. Why do astronauts seem to be weightless in Earth orbit?

24. What is momentum?

25. What is meant by momentum conservation? Give some examples of collisions that simply show momentum conservation (think back to class).

25. What is mass conservation?

26. Why did our friend Aristotle not believe that a vacuum could exist?

27. Kepler showed that Tycho Brahe's astronomical data could be explained using elliptical orbits.

What contribution did Newton make to explaining the presence of elliptical orbits?