I made a video called, “8 General Suggestions for the Free Response Questions of any AP Physics Exam.” And then I proceeded to make video solutions to the 3 Free Response Questions of the 1998 AP Physics C Mechanics Exam and I learned a valuable lesson.  I should have given 9 suggestions.  I should have added a 9th suggestion: “Read Carefully.”

I find it quite funny that I didn’t read carefully enough because (1) for years it is something I berated my students about and (2) it is something I did not do on the third free response question.  You see, I didn’t answer part (a) completely.  I missed the small word “magnitude”.  I simply drew the forces in the Free Body Diagrams, however, I didn’t explicitly solve for the Magnitudes of the Forces.  All the magnitudes of the forces are in my solutions because I had to find each one to solve the rest of the problem; however, I didn’t quite answer part (a) correctly.  I did put the complete solution in my solutions. :)

I don’t know how the AP graders would grade my solution because all the physics is there, just not in the right places; however, I do feel they would not have given my solution full credit.  So, please learn from my mistake and read the questions carefully.  Don’t have to eat humble pie, like me.