## The Questions

February 2 - February 6, 1998

Question #1:

Davidson College's Physics Department runs a very active web-based program. In one of the classes, students conduct an extensive project in which they design and conduct an experiment. They present their findings in the form of a web page which is available for all to see -- even Glenbrook South students who are doing Internet Questions of the Week. For this week's search question, you will visit Davidson College's site and look at a student lab report pertaining to a friction experiment. Log on to theWorld Wide Web and visit http://www.phy.davidson.edu/tomw/final/presentation/title.htm.

This page is the title page for a lab report in which a student has performed an experiment to study the coefficient of friction. The experiment utilizes a variety of principles and/or equipment which we are familiar with such as a sonic ranging device, a two-body/hanging mass apparatus, etc. Much of the physics behind the project should be understandable to you. Click on the link from the Title Page to the Table of Contents Page. Using the Table of Contents page as a home base, investigate the student experiment in order to respond to the following questions. Do a bang-up job on these questions since they are worth two of the three extra credit points for this week.

Respond to the following questions:

1. Discuss the purpose of this student's experiment.
2. Describe the apparatus and the procedure used by the student in order to accomplish the purpose of the study.
3. Discuss the theoretical information which the student was aware of in order to determine the coefficient of friction of the surface.
4. Discuss a few of the findings of the experiment.

Question #2:

A 65-N force at an angle of 25 degrees is applied to drag a 15-kg table across the room. The coefficient of friction between the table and the floor is 0.42. Draw a free-body diagram depicting the forces (direction and type) acting upon the table and calculate the acceleration of the table and the speed of the table after being pushed with this force for 4.0 seconds. Finally, sketch a velocity-time graph to describe the table's motion. PSAYW