Fall 2009 Day 14

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Fall 2009-Day 13
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Day 14 Topics

Diagnostic Question: Falling Objects
Falling Objects
Galileo's Theory
The Rate of Motion
Reflections
Homework Week 7

Peer Instructor Reflection

Fall 2009: Day 14
Written by: Katie Kizer

We started off class by having the students take a diagnostic question on force. The question was something like, “If you have a heavy object and a light object, and you drop them at the same time from the same height, which one will land first and why?” Most of the students wrote that they thought the heavy object would land first because it weighed more, thus causing it to fall faster.

Emily had the students pair up to test out their hypothesis. Each pair was given a heavy object and a light object of the same shape. The students attempted to drop the two objects at precisely the same time from the same height. The other partner watched closely to determine which object hit the ground first. They found that the two objects landed at nearly the exact same time. They found this to be shocking because it went against their initial thoughts about what would happen. The students tried this several times and found that they landed at just slightly different times. They blamed this on human error since the students cannot drop the two objects at EXACTLY the same time.

The students read a skit about Galileo and his theories out loud. I think the students had fun getting to act out the different roles, and it helped them develop a more solid understanding about the mental processes he went through when exploring the effect of gravity. The students realized that the objects fell at the same rate because gravity on the two objects was the same. The heavier object took more inertia to get started, but earth's pull on the two objects is the same, so they fell at the same rate and landed at the same time. At each stage during the skit, Emily checked in with the students and tried to get them to understand the key points.

After this, the students tried to model this (the idea that mass does not affect the rate at which objects fall) by using motion detectors. Students had a slanted track with a cart on it. They put the motion detector at the bottom of the track. Students pushed the cart up and let gravity pull it back down towards the motion detector. A graph showed up on the computer screen. The students repeated this with a different cart that had extra weight on it. The motion detector was not reading the motions very well and the graph looked like a bunch of random jagged lines. If the carts had not gotten derailed, and the motion detector was accurately placed, the two graphs that showed up with the cart and the cart with weights would've looked almost exactly the same. This would have shown that gravity affects objects of different masses the same.

During class today, I learned that unforeseen obstacles with technology can arise and you just have to go with the flow. Everyday in a classroom, challenges are going to occur. Teachers need to be extremely flexible. Not only will technological problems arise, but also as I've observed, students can take the class in a different direction. I noticed that when Adam was teaching the unit on thermal phenomena, he was very open to new ideas and having the students lead the direction to tangents. I also noticed that this allowed a lot of learning happen that would not have occurred if the flexibility in instruction was not there. If teachers were very organized and did not allow for adjustments during class, I think it would greatly hinder the students’ learning. However, some students liked this method of teaching more than others. Some students seemed to feel uncomfortable when there was not an extreme amount of structure. I wonder if this has to do with the way they have been taught while growing up, or if it is a mental factor that everyone has before they are born.