This week on Thinking Thursday I asked you the following question:
then it walks west for one kilometre,
then it walks north for one kilometre
and ends up at the same point from which it started.
What colour is the bear?
The answer, of course, is that the bear is white because it is a polar bear.
Why? Because the only place on earth where a bear can go south, west and north equal distances and end up where it started is the North Pole. Travelling east or west you travel along parallels which are circles equidistant from the poles. And travelling north or south you travel along meridians which are circles that cross both the north and the south poles. Which is all part of the geometry of the surface of a globe.