Why can we feel earthquakes but not feel the Earth moving through space?

Question

I know that we cannot feel Earth’s motion because we are moving with it (i.e. riding in a car with closed windows analogy) but why can we feel the forces on Earth like earthquakes? If we are moving with Earth, shouldn’t we “move” with earthquakes (as they are movements in the Earth’s crust) and therefore not be able to feel them?

Please don’t guess the answer. Only answer if you actually know what you’re talking about lol. I feel like I answered my own Q in my explanation but I need someone more knowledgeable to articulate it in simple words. Thanks!

In: Physics

Answer 1

You don’t feel the Earth moving not because you’re moving with it, but because it’s moving at almost constant speed. If the Earth suddenly changed course or changed speed, like in an earthquake, you’d feel it.