eli5: At constant speed and no vision, are you supposed to be able to tell if you are travelling forward or backwards? How?

Question

Was on the train and it was pitch black outside. Thought I was sitting facing the direction of travel but turned out I wasn’t.

Even when I felt the acceleration/decelerating, I didn’t know which it was.

In: 16

Answer 1

Acceleration in one direction feels like deceleration in another direction. That’s why you couldn’t tell which direction you were facing even when your speed was changing. Beyond that, you can’t feel yourself moving at a constant speed unless air is hitting you or something like that, you can only feel changes in speed.