Teaching General Physics Labs Online

About seven years ago Union County College, Cranford NJ, under the leadership of an exemplary Vice President of Academic Affairs, decided that this comprehensive community college, offering more than 70 degree-granting programs, should be prepared for education in the 21^st century. This initiative led me to taking advantage of generous incentives to develop distance education courses. I first developed and taught online a computer architecture course, then a general physics lecture course, and finally a general physics laboratory course.

I had been teaching these courses face-to-face for many years, and still continue to teach them that way, although less frequently. My first thought was to simply make what I normally do in class available online, except that I would substitute written explanations for verbal ones. After all, students would no longer be able to be enraptured by my wonderful board work but would have to dig in and really figure out how to do the weekly assignments. But I also saw an opportunity to shift the emphasis from teaching to learning, something I had been trying to do for many years, with limited success, with methods like mastery learning and the personalized system of instruction.

To present a laboratory course online required similar thinking. I have never been satisfied that most of my students were learning as much as they should from performing and discussing the results of their experiments. Because students normally work in groups of three, a student could go through an experiment without really understanding what he/she is doing. In the report students could not normally be expected to give an in-depth explanation of the results for each experiment. In addition I never found a way to have them come "prepared" to work in the lab. But when I shifted to an online format, this was easily accomplished.

In the online format each experiment consists of two parts: the first part is a prelab and the second part the lab report. For each experiment students are given a write-up in general terms on what they are expected to perform and what results they then have to discuss. In the prelab they have to discuss some theory pertaining to the experiment, describe exactly what they will be doing, where and how, and what tools or equipment they will be using. Then they have to generate tables for all the data they will be taking and for the results of their calculations. For the measurements experiment, for example, in the prelab the students have to find out what a micrometer is and what Vernier calipers are and describe how and where they are used. They also have to discuss accuracy and precision. Then they have to describe what instruments they will be using to take metric and English measurements of length and of volume of a fluid.

The prelab write-up accounts for 50% of the grade for each experiment and has to be approved by me before the student can proceed with actually performing the experiment. After the students perform each experiment, they resubmit the prelab, with corrections and with the blanks for data and results of calculations filled in, along with a discussion of the results. This lab report accounts for the other 50% of the overall grade.

In the online course, students perform the same set of experiments at home as the students do in the lab. They do measurements, force tables, vertical and projectile motion, friction, conservation of momentum, torque and equilibrium, and Archimedes’ principle. Of course it is a given that students will not be able to take measurements, both distance and time, as accurately as they would be doing in the physics lab. But what they lose in accuracy and precision they more than make up for by having to understand what they have to do before they get to do it. For example, rather than comparing measured to calculated distance and travel time for a projectile fired from a launcher with a known initial velocity, they have to calculate that initial speed and angle based on how high a thrown ball rises and where it lands. Before they can perform the experiment, they have to make up examples and calculate the trajectories to give them some idea of what to expect when they actually release the ball.

So, not only have I found that it is possible to offer a mechanics laboratory course online, but doing so presents some distinct advantages over experiments scheduled in the physics lab. Of course both courses have to adhere to the standard semester schedule, but because online students can work whenever they find it convenient, they have more flexibility in catching up if they are delayed or even work ahead; in a traditional course I cannot turn away a student who comes unprepared to the weekly lab. Online students have to properly prepare for performing an experiment and they have to convince me that they understand what they will be doing before they do it. They have to be resourceful in developing the facilities and the procedures for each experiment instead of having it ready when they walk into the lab. They are forced to not only learn but to think as well. And isn’t that ultimately what teaching is all about?

Prof. Bohdan Lukaschewsky

Union County College

Cranford NJ 07016

908.709.7537