"Physics" is a fairly artificial concept of separation of knowledge - after all, knowledge is just one. Our brains, on the other hand, are too tiny to fit all of it in. We started learning about surroundings "midway", e.g. F=ma - basic physical phenomenon, and from there started moving towards the very small (quarks), very large (galaxies), and much more complex - chemistry, biology. I think the discoveries tend to go in waves, and when there is an imbalance of knowledge, the area at the bottom shoots up. For example - enough data accumulated and enough mathematical tools were developed to boost physics and chemistry, which helped with computers, which in turn boosted biology. Next step - exact predictions of social sciences, terraforming, ... Time to travel far far away.
P.S. Even though I couldn't find who was the original author, my physics teacher once told me that when governor visited Franklin's lab, and was shown all the electrical research, he wondered what was the purpose... to which Franklin replied "Physicists will tinker with it for a bit, and later you will start taxing it". It might have been someone else of course, but does not change the point - something gets discovered, and later it becomes ubiquitous in our everyday life.