Posts tagged teaching

        take one of each…

Some definitions: 

phenomenon: A fact or situation that is observed to exist or happen, esp. one whose cause is in question.

physical phenomenon: A “natural” phenomenon involving the physical properties of matter and energy.

<teaching rant>

Today we are beginning our exploration of electro-magnetism.  In this overarching theme there are topics such as magnetic fields, charges in magnetic fields, magnetic flux, Faraday’s law, Lenz’s Law, electromotive force (EMF), generators and transformers.  Don’t worry if you don’t know what these words mean.  They are just words with vague connotations at this point.  Our job is to understand the physical phenomena that relate to these words, and apply our understanding to answer quantitative problems (problems that have numbers in them) that are based on these physical phenomena.

To start this topic off, we are performing an exploratory activity where you will manipulate objects at your desk, such as metal, plastic, and magnets, and will answer a series of questions that will guide you through your observations.  This will help you realize the myriad of physical processes that are happening right in front of you so that your understanding of magnetism is as strong as possible as we move through the next 3 weeks.  The goal is to get a good set of observational and mental pictures of the basic nature of magnetism under your belt that you will use as the underpinning of all the subtopics mentioned above.

Most physics classes that you would take assume that you already have a strong set of “observational and mental pictures of basic nature”.  The class usually jumps right into formalizing these observations into definitions, terminology, and relevant equations.  If it does talk about the physical observances that underpin the phenomena, it is usually just a reminder of things you have already seen in your life.  Or, there may be demonstrations shown in the front of class, which nicely shows the phenomenon.  Or, there are statements of a set of progressing steps which connect the new topic (magnetism) to things previously learned in the class (static electricity, forces, etc.).

The problem with this instruction is that this is too mentally taxing within the speed that it is being given.  There is usually too much need for a rapid assimilation of mental recall of prior life experiences,  recall of things you learned recently learned in class, and new terminology and equations.  Mind you, being able to perform this assimilation quickly is very valuable and is a skill to hone (especially when going into the field of medicine).  But if you don’t have incredibly good recall of incredibly good observations of physical phenomena, you start to sink quite quickly.

I should say, about 10% of you can do this.  You may have spent hours playing with magnets - just playing with them - while you were growing up.  As easily as you spend hours playing with interacting with friends or playing a sport,  you were just playing with something that shows the interesting physical phenomena that is magnetism.  Maybe even by accident… in front of a refrigerator.  And, you may have good recall of these memories, almost a picture perfect representation of what you observed when you were younger.  For those 10% of people in the class, you have a much stronger underpinning to see the invisible, to visualize the problem better, to know which direction to “go” for each problem, to set up force diagrams with more ease, and to get the right answers on tests.  You aren’t “smarter”, in the sense that you are quicker and have a higher capacity for learning.  Rather you spent time playing with certain things when you were growing up and you have a huge head start.

So here we are in physics class, introducing a new concept, and one of my goals is to not just have 10% of you be comfortable and confident about this topic.  You also need to know that you can be as quick and visualize things as good as the 10%, but it takes lots and lots and lots of training, observation, and thinking, in your spare time.  There should not be a moment when you are not doing this in college.

Research has shown that a good amount of comfort and confidence of these topics can start by you just playing with magnets for hours and hours, feeling them in your hand, feeling their repulsion and attraction, seeing how they interact with each other and other things, see how their shape affects their interaction. etc. etc.  But we do not have time.  We are running out of time.  So what is the next best thing?  One answer is to intensify these experiences into a few hours - to see the phenomena happening in front of your eyes with a well informed teaching staff able to guide your observations to really make you think about what you are seeing.  

        exploring magnets with Tutorials in Introductory Physics

The Tutorials in Introductory Physics from the University of Washington Physics Department are the least flawed way for us to do this in the limited amount of time that we have.  They are a way for you to attempt to hone all of the observational experiences that you have had about magnetism (and if you haven’t had any experiences, give you a crash course in the phenomena right in front of you), and to tease out the complexities of observation about magnetism that are necessary for you to be be successful and confident for the next 3 weeks.  This is one of our major attempts to enable you to do more than just blindly apply equations to try to solve problems.  This is not the end all of the instruction.  Also, it is not perfect.  But it is the best we can do with an hour or so of having experiences in the classroom.  I should point out that a lot of good research has gone into making these tutorials as learning-rich as possible.

I also will give you magnets to just play with at home (similar to the wires and bulb and battery that I gave you when we were learning electricity).  This is another way for us to catch up: just by you playing with something physically interesting while you are watching TV, or at the dining hall, or reading.  WARNING: you shouldn’t put magnets near any electronic devices.  For small magnets, keep them about 6” away from electronics.  Here is another one of our challenges to really understanding things: in our current advanced world, things (like magnets, electricity, lasers, radioactivity, the list goes on and on) that could help us understand this wonderful world we live in better, can also break certain things or hurt us if we aren’t careful.  They are therefore deemed dangerous, and we don’t usually have them to explore in our lives.  This is a concept that chronically stifles many aspects of our development, and you should be mindful when it is happening to you.

With all of this said, here is the main point:  These exploratory activities are not a touchy-feely, feel-good way to understand the material.  Rather, these activities are possibly the ONLY way for a large majority of you to connect - in a very robust, enlightening, and empowering manner - the actual things that are happening in the REAL world to the equations and numbers and problems that are happening on the REAL test.  Another major point: these activities are not a license to goof off and not have your brain work as hard, just because there are no equations.  Don’t just use the fact that there aren’t numbers somewhere in a problem or activity to activate your logical awareness.  That is a huge mistake.  These activities are actually quite challenging and require all of your mental capacity, and even then we are going to fall short.  So don’t skimp on anything related to them.  In fact, you should be putting more effort and investment into answering these problems compared to any random question that has a numerical answer, because once you get these underpinnings down, your job of solving problems with numbers becomes much less overwhelming.

see you in class.

</teaching rant>