posted by g on .
imagine a flat, lightweight wheeled cart that's low to the ground and has well-oiled bearings. what would happen if you approached the cart, stepped onto it, and walked along its length at a constant speed? it would
a) remain nearly stationary
b) advance along with you
c) move rapidly in the opposite direction
d) move forward then backward
e) none of the above
it would move in the opposite direction due to conservation of linear momentum, but I don't really know why it would be considered 'rapid'...