March 11, 2011- How things slow down

First of all, I don't know if this will be the best describtion of everything because I don't feel good today.

We started by going over our homework.

Mr Finley put the correct answers on the board, and our goups had to talk about them.

The correct diagrams where :
DOT
a. ._.__.___.____.______.________.

b. ._.__.___.____._______.________.

c. .

d. .__________._______.____.___._..

e. ._._._._._._._._._._._._._.

FORCE

See someone else's notes.

Then Yolanda asked why E slowed down. Wouldn't the ball just stop in the hand?

The answer is no, no matter how light an object is, when your hand catches it your hands go down a little bit, depending on the weight. When an object stops, first it has to slow down. We watched this video to prove it. Only the beggining matters for what we are doing in class.

Video- http://www.youtube.com/watch?v=QfDoQwIAaXg

Then to explain this futher Mr finley threw an orange. As it goes up the orange slows down, and the top it almost stops, then it goes down speeding up.

Then we pushed a ruler across the surface of the table. After a few seconds it slowed down. This was because the surface of the table had a negative force on it. At the same time there were three different forces on the ruler. (let's say you slided it to the left) There's the table holding the ruler up going up, the pull of the Earth on the table going down, and a force from the table surface going to the right.

This slowing down right before stopping concept confuses me alittle, and the fact that force diagrams can have more than two arrows goind multiple directions is something I have to remember because it makes me think that sometime aren't solutions to things there are soloutins to. I just need to look at my notes again and then I'll understand it.

Here are some interesting websites:
http://www.physicsclassroom.com/class/1dkin/u1l5a.cfm
http://www.physicsclassroom.com/class/1dkin/u1l1e.cfm
http://www.physicsclassroom.com/Class/newtlaws/

DB(4TH)