Professor Mason spent the first 10 minutes of class introducing himself and describing his background.
- He started in Electrical Engineering
- He worked in design and instrumentation for X ray detectors.
- He did his graduate work in Physics
- He worked for a company that made bearings
The class was asked to define Science.
- Science is based on experiment
- Science is the study of nature
- Good experimentation has certain requirements
The class was asked how to prove something to be true. Professor Mason picked on every answer until it was apparent that proving truth was not possible according to his definitions.
The class was asked to judge how a mass on a spring attached to a cup would move if the cup was dropped. People drew free body diagrams to analyze the system.
The class was asked to define reality. There was general agreement that reality is personal and thus different for each individual.
Students were asked about to analyze how a meterstick would fall if its points of support were moved.
After a break we did a lab on using the Logger Pro and Video analysis.
Learning to use and setup LabPRO.
1. My group and I were given the task to measure acceleration due to gravity on a motion detector, and acceleration due to gravity from vidoe analysis.
2. We began by setting up the motion detector and opening up Logger Pro to record our graphs and data. Once we had a correct setup by adjusting some some rates, we began experiminting.
3. We began an eperiment with a ball, meausuring acceleration due to gravity of the falling ball. I held the ball just below the motion detector and one of my group members hit the collect button to collect data and i released the ball about a second the motion detector started clicking.
- We observed our graph displayed
- We then highlited the part where the ball was going down (stright line) , ignoring the bounce
- We fit a line to the graph, which gave us the slope and itercept
4. The results of our graph gave us the equation y=mt+b, were the slope of the graph was the acceleration, and the b was the y intercept (being 0). So we saw the connection of the equation V=at+vi. In our results our acceleration calculated to be 10.53 on the inital slope, but we also looked at the line after the bounce to have 9.87, we took an average of the two and got a calculation of 10.2, wich was reasonalbly close to the actual value of acceleration.
Video analysis
1. After completing the motion detector experiment, we used little cameras to record a bouncy ball falling towards the floor. We set up our lab by connection the camera and adjusting the settings to take a 5 second movie, adjusting the gain to the max(about 255 i believe), adjusting the shutter to 1, and changing the exposure to manuel with a value of 150. Now we were ready to experiment by making a movie.
- My group member was set to shoot the video, the other was holding a meter stick, and i was holding the ball to be released.
- We began to shoot the movie having some problems with pixels, and after some help from our professor we realized there was a chat program running taking away about 100 pixels.
- We finally shot a movie with 148 pixels and played it in slow motion allowing us to see the ball falling with no smudges.
2. We then opened the video analysis tools, and had a graphed displayed. The graph displayed position vs. time, and from here we set up to see the y-axis of the graph. We set a scale of 1m, wich was the size of the meter stick, and added pts. to were the ball began to fall from my hand till it almost hit the floor, and after we did that we played the video were it also gave us the position(y axis) vs. time and saw a parabola graph.
- We fitted a curve fit line to the graph
- We aquired our data having -5.2 being the acceleration to be -10.4
3. Then after the experiment professor Mason gathered different data of acceleration comparing them and taking an average. We also observed how there was a margin of error in calculations wich needed to be adressed, and so he adressed it to be + or - .056
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