In 1974-1975, the multiple-choice sections of both parts of an Advanced Placement (AP) Physics C Examination were given as parts of final examinations to college students completing the appropriate semester of an introductory calculus-based physics course. Almost 3800 candidates were tested in 15 highly selective colleges. The college students scored on the average about the same as or slightly lower than the AP candidates who also took the same exams and the scores of the college students correlated quite well both with end-of-course grades and with rankings of the students' physics achievement made independently by their instructors. The equivalencies between AP and college grades were estimated, both for mechanics and for electricity and magnetism. An AP grade of 4 or 5 was roughly equivalent to a college A, an AP 3 to a college B, and an AP 2 to a college C.