When math fights physics pacifies

Since we have to place math books between physics books, there are 7 places (6 + 1) that would be formed between the physics books. Now, we have to choose 3 places for math books from these 7 which can be obtained by $^7{\text{C}}_3 = 35$ .
Now, the physics books are distinct and thus can be arranged in $6! = 720$ ways.
Similarly, the math books are distinct too and can be arranged in $3! = 6$ ways.

So, the total number of ways in which the books can be arranged = $35 × 720 × 6 = \color{#3D99F6}{\boxed{151200}}$ ways.