How do you know if someone far away is walking towards you or away

dimanche 1 septembre 2013

This is something trivial that has been bugging me for a while. When someone is far ahead of you on a sidewalk, you see their arms swinging and feet beating the ground. But how can you make out if they are walking towards or away from you?

Suppose that I don't want to stand still for thirty seconds to see if they're getting closer.






via Physics Forums RSS Feed http://www.physicsforums.com/showthread.php?t=708109&goto=newpost

0 commentaires:

Enregistrer un commentaire