10/17 MS Physics update and homework due 10/24

Hi folks,

Gravity is a big topic and today we spent some more time really getting into it.  We talked about the difference between mass and weight and we talked about what weightless really means.  We also spent a bit of time with a couple of formulas.  We went outside and threw a ball straight up.  Then we came back inside and spent some time with two formulas to see how fast our throw was and how high our throw was.  The point of the math at this level is to just see that math is a tool that can be used to look at real world problems.  Math is more than just problems in a book.  Don't worry about the math on quizzes or homework the students won't be graded on it.

For homework this week, read the Gravity chapter (Pg 23) and the Acceleration chapter  (pg 54) in the Bite-Size Physics book.  Please do all the questions, except for the math ones at the end of both chapters.  Please read the "Deeper Lesson" part of the gravity chapter as well.  (Again…don't worry about the math.)  By the way, feel free to do the experiments but you don't have to for homework.

If you'd like some extra credit and would like to try your hand at some of the math for the gravity chapter let me know.  I'll whip you up some problems to solve.

Last but not least, please answer these questions based on today's lecture.

1.  What is the definition of mass?

2.  What is the definition of weight?

3.   If you go to the Moon, which changes; mass or weight?

4.  Remember the idea of Newton's Cannon?  That cannon on top of the mountain that shot farther and farther until it went around the world?  What did that have to do with the moon? 

Answers

1.  The amount of material (atoms) in something.

2.  How hard gravity pulls on something.

3.  Weight changes, mass does not.

4.  The idea is that the moon is falling towards the Earth, but it's moving so fast that it just keeps missing.  Just like the cannon ball.