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This Week: Here's how it works. I will post a new
Brain Teaser for classes on Sunday evening of each week. These Brain Teasers will be available for the whole
week and are good for extra credit. All you have to do is read the Brain Teaser, fill in the appropriate response
section below, and submit your answer. All submissions go directly to my school e-mail. Be sure to include your name!
(I can't give credit to ghost writers.) If you include an e-mail address, I will respond to your submission. Have fun!
BRAIN TEASER:
Blocks 3 & 4:
Many of you have told me that my responses to you are ending up
in your spam folders. I will generally respond to you WITHIN TWENTY-FOUR HOURS, so PLEASE check your spam
folder for a response if you do not receive one in your inbox. This is especially important in case your answer is incorrect
since I will give you hints and another opportunity to get the extra credit. Have fun!



We played with momentum a bit last week when we used the wind-up toys for a short lab. We
will be looking at this concept more closely this week as we continue our experiments with the ramps and photogates. As such,
I would like you to delve a little deeper into the concept of momentum.
If you don't already know, momentum is conserved. "What does THAT mean," you ask? That's
what I would like you to investigate and explain for this week's Brain Teaser! Here's what to do. Do an Internet search for
"Momentum and Its Conservation" (be sure to use that exact phrase). Now, read through the material you find and write
a good definition for conservation of momentum. Next, give a good example showing how conservation is conserved.
Have fun!
We've been working with speed and velocity--specifically, the difference between the
two. After the "Break" we will add acceleration to our studies. (Yea!) As an "hors de oeuvres" to whet your appetite, take
a look at Image 1 below.
First, remember that velocity is "direction aware" and that the direction is represented
as a vector. The "tail" end of the vector represents the starting position while the "arrowhead" end of the
vector represents the direction of travel. You will see that the image above has a vector for velocity. Now look
at the graph. It shows that velocity is constant, so acceleration is zero. Now examine Images 2 & 3 below.


Both images have velocity
AND acceleration vectors. the degree of each (velocity and acceleration) is shown by the size of the vectors relative
to each other. (In other words, the larger vector arrow has greater value.) Keep this in mind as you embark on your
quest for this week's two-part Brain Teaser!
Examine Images two and three carefully and then determine what each graph
would look like. Write a brief description of the resulting line. (Example: The line in Image #1 is
moving from the bottom right corner of the graph toward the top right corner.) Next,
explain what the motion of the car would look like. (Example: The car in Image # 1 would be moving
toward the top of the screen.)
The graph for Image 1 would slope upward from the left to the right, and the car would
be moving forward (from left to right across the screen). The graph for Image 2 would slope upward initially and then downward
from left to right. The car in Image 2 would move forward initially and then begin to move backward.
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