Halliday and Resnick's "Fundamentals of Physics" is being used by a participant preparing for the USAPhO, with questions about its sufficiency for achieving semi-finalist status. There is a discussion about the differences in difficulty between the "Physics" and "Fundamentals of Physics" versions of the book. Clarification on the specific edition being used is suggested for more tailored advice. The new test, referred to as "F = ma," raises questions about its focus on mechanics. Overall, users are seeking guidance on whether additional resources are necessary for effective preparation.