Yes, previous year question papers for the UPSC Physics Optional subject are available.

1. UPSC official website:
The Union Public Service Commission (UPSC) releases the previous year question papers on its official website. Candidates can visit the UPSC website and navigate to the 'Previous Year Question Papers' section. From there, they can select the Physics Optional subject and download the question papers in PDF format.

2. EduRev:
EduRev is a popular online learning platform that provides previous year question papers for various competitive exams, including UPSC. They have a dedicated section for UPSC Physics Optional subject, where candidates can find and download previous year question papers. The platform offers a wide range of question papers, which can be filtered based on the year of the examination.

3. Online forums and communities:
There are several online forums and communities where UPSC aspirants share resources and discuss preparation strategies. These platforms often have sections dedicated to previous year question papers. Candidates can join these communities and interact with fellow aspirants to access and exchange question papers for the Physics Optional subject.

4. Coaching institutes:
Coaching institutes that specialize in UPSC preparation also provide previous year question papers for the Physics Optional subject. These institutes often have their own study materials and resources, including question banks and test series. Candidates enrolling in these institutes can access these question papers as part of their preparation material.

It is important to note that while solving previous year question papers is a valuable part of the preparation process, candidates should also focus on understanding the underlying concepts and theories. Merely memorizing the answers to previous year questions may not be sufficient to score well in the UPSC examination. It is advisable to refer to standard textbooks and study materials recommended for the Physics Optional subject to build a strong foundation in the subject.