For B. Sc. Physics(Hons.)  or chemistry (hons.), you meet the eligibility criteria. 

Your percentage will be calculated for English, Physics, Chemistry and Maths which would be 77%. 

77% marks are not good enough to get you a top DU College but you can wait for the last cutoff lists for various colleges. For top colleges, cutoff won't fall below 88-90%.

Also, don't lose hope if you don't get admission in DU. There are various other Universities and good colleges where you can apply directly or take the entrance tests, like the BHU Entrance Exam, etc. If you wish to know about other exams, you can let me know in the comments. 

You can check the link below for eligibility criteria for admission in various courses in DU:

https://university.careers360.com/articles/du-eligibility-criteria

To know more about your chances you can check the college predictor link below:

https://university.careers360.com/delhi-university-college-predictor

Hope this helped. All the best.