It's hard to say, but physics competitions are more useful. Taking part in the physics competition is not to finish college physics in advance, but to finish college physics (and advanced mathematics) in the process of learning. (The physics of general engineering is very simple. Look at the physics department. ) The physics competition is mainly about reading books and doing problems. I recommend several books I have read, the first one is Fan Xiaohui, the third one is Advanced Mathematics for Beginners, and the fourth one is a collection. The three books compiled by Cheng Jiafu, including lecture notes, mechanics and electricity, should be carefully read again and again. You have the strength to win the prize. The fifth book, Higher and Better Physics, is a rare good book. You must do the sixth book, The Problem Set. Shu Yousheng also has a little red book compiled by Zhu Hao. I can't remember the names of all the questions above. What is hard to do is the sixth extra-curricular book "New Concept Mechanics" and "New Concept Electromagnetism" compiled by Zhao Kaihua. In fact, they are all textbooks read by physics department as extracurricular books, but there are also useful ones, such as Coriolis force.