It’s actually because the thing that makes you make those faces is the acceleration, not the speed.
All three reference frames shown are accelerated, non inertial frames. But the first two have “fictitious” centrifugal accelerations somewhere around 0.5-2.5 g. The third frame has a detectable centrifugal acceleration, but it’s like 0.003 g or something, and can be lumped in with gravity for many types of problems.
It’s actually because the thing that makes you make those faces is the acceleration, not the speed.
All three reference frames shown are accelerated, non inertial frames. But the first two have “fictitious” centrifugal accelerations somewhere around 0.5-2.5 g. The third frame has a detectable centrifugal acceleration, but it’s like 0.003 g or something, and can be lumped in with gravity for many types of problems.