The purpose of this study was to investigate the effects of the flipped classroom on optimizing students’ motivation and understanding of medical physics concepts. This approach transfers teacher-fronted lessons out of class to be prepared by students at home and utilizes their class time for discussion and practice. The sample included 123 female students: 58 in a flipped classroom and 65 in a conventional classroom. Three instruments were developed: teachers’ guide, an understanding test, and students’ motivation questionnaire. Data were analyzed using the mean, standard deviation, ANCOVA - test, and size effect. The results showed that there were statistically significant differences among students’ increased motivation and understanding of medical physics concepts in favor of the flipped classroom learning. Therefore, instructors and curriculum developers should restructure the contents of their courses according to flipped classroom principles to foster students’ motivation and understanding of medical physics concepts.