Does the interest of students arouse motivation or vice versa? What theory supports this idea? Can social-cognitive theory help to increase the level of interest students have in a particular subject?
Fostering interest has long been an objective in the design of informal science education, as it is an outcome uniquely suited to free-choice learning activities (Bell et al., 2009). Rather than merely positive emotions or momentary attraction, interest includes stored knowledge, stored value, and feelings that influence both immediate and long-term engagement, questioning behavior, and activity of individuals or groups of individuals around a specific topic. Interest always leads to motivated behavior (Renninger, 2007, p. 5).
With motivation, participants begin to ask curiosity questions and seek answers as they engage with content (Renninger, 2007, p. 2). Within a “learning ecology” composed of learning opportunities in the home, community, peers, work, school, books, and virtual resources (Barron, 2006), people become active in structuring and extending their own learning, using their discretionary time to engage in their interest. Such was the case of self-sustained learning for three focal adolescents, for whom researchers identified five strategies of engagement: text-based informational sources, the creation of new informal activity contexts, exploration of media, the pursuit of formal or structured learning opportunities, and the development of knowledge networks such as mentoring relationships (ibid).
With your knowledge of physics, you could design an experiment to study the response (motivation or interest) to stimulus (interest or motivation). Good luck! Of course, the topic interests me so much. If you do some work in this area, please share with me.