Force and Motion: Stop Faking It!

Newton's Third Law and Circular Motion!
The second of two Web Seminars on the topic of Stop Faking It! - Force and Motion was held on Wednesday, February 1, 2006, from 6:30 p.m. to 8:00 p.m. Eastern time. The session was presented by Bill Robertson, author of the popular NSTA Press series of books Stop Faking It! - Finally Understanding Science So You Can Teach It.

The session started with a general overview of the Web Seminar tools and how they can be used to facilitate interaction between the participants and the presenter. Eighty participants were present in addition to Bill Robertson and the NSTA staff. Educators represented the states of Arkansas, California, Colorado, Florida, Illinois, Kentucky, Louisiana, Maryland, Massachusetts, Minnesota, Mississippi, Missouri, Montana, Nevada, New Hampshire, New Jersey, New York, North Carolina, Ohio, Oregon, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas, Utah, Virginia, Washington DC, and West Virginia. One participant joined us from Canada.

Bill talked about Newton's Third Law of Motion and Circular Motion. For Newton's Third Law, Bill used a few examples to explain the idea of "equal and opposite reaction." First he talked about a balloon filled with air, and how it "flies away" if you let the air inside free. Then he used an example with a donkey pulling on a cart. Bill also used a simulation from one of NSTA's Science Objects (currently in development) to give participants the opportunity to manipulate variables and observe the behavior of two carts moving on an air track. In explaining circular motion, Dr. Robertson talked about centripetal and centrifugal forces. To make the concept of centrifugal forces more clear, he described the idea of reference frames. For a person riding a merry-go-round, the centrifugal force, pushing away from the center is real. However, for an outside observer, Bill explained, the centrifugal force doesn't exist.

Throughout the presentation there were several opportunities for interactions among the participants and presenter - chatting, stamping the best answer, making arrows to represent forces, experimenting with a simulation, and interacting verbally with each other.

Here are some comments provided by the participants at the end of the Web Seminar:

• "Interactivity is definitely the way to learn today. The capability of blending the
online interactivity with the phone conversation was excellent and exciting.
Thanks for sponsoring this event. I anticipate more to come."
• "This was the first time attending a web seminar. In my state, little time is available to teach science effectively. The information I received tonight will
help me make Newton's 3 Law more efficiently and stimulate the interest
of my students."
• "The seminar was very easy to use and to log in to. I think the time allowed
before was great in getting everyone familiar with it. I love the fact that it
was interactive in so many ways (visually, and text, and
verbal). Keep them coming!"
• "The whole process was really interesting for me. I don't get to attend the national
conferences. That limits a lot of my national networking. It was really great to get to touch base with so many teachers from all over the country."

Thanks to the participants and Bill for the learning opportunity, the interactions, and a job well done!