From my personal experience, some basic physics knowledge can help a lot to tune your game.
Lets say that you want to create certain physical effect in your game e.g. players can push boxes. Of course, you need to tune certain parameters to make this effect behave as you want, so that the boxes neither violently fly in every direction neither are almost impossible to move.
You can try trial and error, but besides being a boring way to tune parameters, it will make your code brittle: if something goes wrong, you won´t even know why.
On the other hand if you know how physics work, you can easily do the math and plug in the values to achieve the desired effect.
TL;DR: If you want to provide any physical effect in your game, it helps to learn the basics.