To determine which college you can get admission to with a score of 52 marks in the RUHS B.Sc Nursing exam, you'll need to consider several factors:

1. Cutoff Marks: Check the previous years' cutoff marks for different colleges under RUHS. This will give you an idea of the scores needed for admission in various colleges.

2. Category: Your category (General, SC, ST, OBC, etc.) will also play a significant role in the admission process, as there are usually different cutoffs for different categories.

3. Availability of Seats: The number of seats available in each college for the B.Sc Nursing course will also impact your chances. Some colleges might have more seats, making it easier to get admission with a lower score.

4. Counseling Process: During the counseling process, you should list your preferred colleges in order of priority.

To get a more precise answer, I recommend checking official resources, such as the RUHS website, or contacting the counseling authorities. They may provide updated information on the cutoff trends and available seats for the current year.