These days seem to go so fast, at least for me. Today was a friction day in the O, W, and S sections. We went over HW, which covered the topics of friction, gravity, and free fall. There are four types of friction: static, rolling, fluid, and sliding friction, but all are basically the same: a measure of the force it takes to overcome the resistance to motion between two surfaces. This leads into a discussion of the universal law of gravitation, the idea that gravity exists between all objects at all times. This leads to free fall, which is confusing. Objects will fall at the same rate as long as resistive air forces do not hold them up. So a marble and a car will hit the ground at the same time dropped from the same height. In reality, it doesn't happen, because the car is not nearly affected by air the way a marble is.
We looked at a free fall laboratory on Explorelearning.com which was cool--you can drop different objects from a tower and see which hit first. Very cool. You can check out explorelearning at home using the links and directions to the right of this blog.
The L section did a great job with the marble lab. Their graphs look great, a telling sign that their data was collected well.
Sweet justice.
