why can we see airplanes moving slowly from the ground but they are too fast
Answers
Answer:
Because the perceived distance issues. You are feeling of the distance covered is trivialized because the distance to the plane is beyond the parallax capabilities of your eyes. What this means is that effectively without some means of perspective or size measurement anything over about 1000m is hard to judge and for most people it is impossible to tell the difference between a plane flying at 3km or 10km high. (I have had people accuse me of flying over their house at 100 feet when ATC has me at 1500 feet.)
The net result is that it feels like the plane is traveling at about 1 tenth of it’s actual speed due to the lack of known objects to add perspective.
The same is true for being in an airplane flying over the ground, because you can see so much of it you can feel like you are almost stationary.
