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Posts tagged “labs”
Compilation of Posts to the Modeling Listserv
Appears to be an outstanding resource for labs and modeling. Definitely the direction I would like to take my physics classes. I was the articles weren’t PDFs.
“ We have adopted a similar line of thinking in our intro labs. Instead of providing them, though, with a task such as the pendulum clock, we provide them with a goal (either a measurement or a test of a particular mathematical model) and then let them decide to some extent how they are going to go about testing the model or making the measurement. I found that this paradigm works very well in the intro E&M labs. I provide students with a goal- for example, measure the charge-to-mass ratio of the electron. Then, they get to figure out how to measure it given available equipment, what kind of data to take, how much to take, and how to process it. This same paradigm works well for other types of experiments such as:
1) measure the capacitance of a capacitor
2) determine if a device is an ohmic resistor
3) determine if the electric field is indeed uniform in a parallel-plate capacitor (model testing)
4) measure whether the electric force is proportional to 1/r^2 (model testing)
5) measure whether the magnetic field is proportional to a current (model testing) It works very well to give students a pre-lab workbook that helps them work through some of the equipment setup and functioning before they come to lab. The students have responded well to the labs and I think we have better engagement and understanding in the labs. ”
“ You are in a stationary vehicle (a train, bus, or a large vehicle). You have a helium balloon attached at the end of a length of string, so the balloon floats freely (without being confined or rubbing against other objects), while you hold the other end of the string. The vehicle then accelerates forward. What happens to the balloon? ”
“ Each instrument has an inherent amount of uncertainty in its measurement. Even the most precise measuring device cannot give the actual value because to do so would require an infinitely precise instrument. A measure of the precision of an instrument is given by its uncertainty. As a good rule of thumb, the uncertainty of a measuring device is 20% of the least count. Recall that the least count is the smallest subdivision given on the measuring device. The uncertainty of the measurement should be given with the actual measurement, for example, 41.64 ± 0.02cm. ”
