## The Questions

January 13 - January 17, 1997

Question #1:

As we approach the topic of forces, you should continually be aware of the fact that you have begun the course with a variety of preconceptions. You have already formulated a variety of ideas about acceleration, mass, weight, force, gravity, etc. Your task of learning the concepts taught in this course demands that you continually contemplate your own beliefs and deal with them accordingly. This week's Internet search question will target the topic of student preconceptions. You will visit a site which you visited a few weeks ago, titled Comprehensive Conceptual Curriculum for Physics (also called C3P).

Find the site titled Comprehensive Conceptual Curriculum for Physics (also called C3P) using a major search engine. The site is based at the University of Dallas, the prinicpal investigator is Richard P. Olenick, and it is a common high school physics education site. This should be sufficient information to find the site using a keyword search. Once you find the C3P home page, click on the button titled Alternate Student Conceptions. A variety of student preconceptions are listed on the linked page. The list identifies the most common misconceptions believed by students of physics. Note: these are MISconceptions - wrong beliefs. (A word to the wise: this would be an excellent page to print and to keep available as a checklist as you proceed through the rest of the year. If you believe any of these ideas, then you will likely have difficulty.)

Once you have found the site, do the following:

1. identify the URL (address) of the Alternate Student Conceptions page.
2. describe the search path which you took to find the page (see example description).
3. review the preconceptions for the Newton's Laws/Forces section and study the preconceptions listed under this heading. For three of these preconceptions, write a few sentences in which you state the preconception and describe a concrete example which illustrates why such a preconception is a false conception.

Question #2:

A 50-Newton force is applied to horizontally accelerate a 20-kg object across a level surface. The mass encounters a 38-Newton force of friction. Draw a free-body diagram showing the types and direction of the forces acting upon the object. Calculate the acceleration of the object. Finally, sketch a velocity-time graph to describe the object's motion. PSAYW