In recent years, diversity, equity, and inclusion (DEI) have gained increasing importance in the field of physics. Despite efforts to enhance DEI, physics still faces numerous challenges in this area. This dissertation is divided into three main chapters, aiming to investigate the significance of learning-related emotions and physics identity as means to improve DEI in the field and gain a comprehensive understanding of students' experiences while working in groups. The first chapter delves into the concept of being a "science person" by presenting a taxonomy developed using the extensive literature on science identity, which is then applied to research on physics identity. The subsequent chapters focus on understanding students' learning-related emotions in the context of groupwork within their introductory physics courses. The study includes students from algebra, calculus, and honors mechanics and E&M, who were recruited to explore how interactions between students can influence their emotions and other affective constructs, such as self-efficacy, conceptual understanding, and perceptions of effective groups. Control value theory serves as the theoretical framework to investigate these relationships. For this research, a mixed methods approach was adopted. A survey was administered to students in the Fall of 2021 and Spring of 2022, utilizing a modified version of the achievement emotions questionnaire to assess their learning-related emotions. Students were also given the option to volunteer for an hour-long Zoom interview. Quantitative data was analyzed using confirmatory factor analysis, ANOVA, and t-tests, while qualitative data was analyzed using thematic coding. The study's results revealed no significant differences in learning-related emotions based on gender or race. However, statistically and practically significant differences emerged when students were grouped by their sense of belonging. Furthermore, the study highlighted the importance of productive struggle in creating positive groupwork experiences. This indicates that experiencing some negative emotions can be beneficial to students' attitudes towards physics and their perceived achievement. These findings suggest that instructors need to be intentional when forming groups and designing curriculum to foster a supportive and inclusive learning environment. Overall, the study underscores the potential of learning-related emotions and physics identity in enhancing DEI in the field of physics. By recognizing and addressing the role of emotions and identity in the learning process, educators and institutions can take meaningful steps towards creating a more inclusive and supportive physics community. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]