Monday, October 4, 2010

Blog 3



On Friday, October 3 2010, my physics teacher, Mrs. Chen had a substitute by another physics teacher, Doc. For a real life example of the lesson, he made the whole class ride the elevator. As we went up to the third floor from the first, we could feel our bodies getting heavier for the first few seconds. Later during the ride, we felt normal, and finally after that we felt lighter. These changes that we experienced are caused by the change in our normal force. When we are just standing, we have two forces acting upon us: normal force and our weight. Normal force is the force that negates the force of gravity. On the elevator, our normal forces rose and stayed constant for a while before decreasing back to a halt. The normal force affected our net force and our net force changed our acceleration. As we accelerated upwards, our normal force rose making us feel heavier. When the acceleration became 0, our normal force also became 0. When we slowed down before reaching the fourth floor, we felt lighter because our normal force decreased. We also felt this as we went back to the first floor but in the opposite order. The same thing can be said about a scale. When I push down on the scale, the scale reads higher but when I don't push down as much then the scale reads lower. The scale is reading the normal force. I can't fix this font...
 With less normal force.
 With more normal force.
Normal Normal Force.

4 comments:

  1. Great job explaining why all of this happens. I never would have thought of any of this while in an elevator.

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  2. Nice blog
    didn't realize how much physics there is in a simple elevator

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  3. i wish i read this before the test on friday..

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  4. that's a pretty nuts scale. I'm surprised you read your numbers backwards

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