nisen20 wrote:
jaykayes wrote:
IMO, I don't think there's any ambiguity on that aspect - isn't west always perpendicular to north? Or am I missing some scenario where west is NOT perpendicular to north?
Yes. I agree, if we are only talking about two directions.
Traveling west and then north, presented in the prompt, is different. The two highways could be perpendicular to each other but
not must be, because we are not living on a chess board formed by some vertical and horizontal lines.
When we talk about heading north in real life, do we really mean to move towards the North Pole with no deviation?
Yes, we
ARE in fact living on a giant (curved) chessboard with (imaginary) vertical (longitude) and horizontal (latitude) lines on it.
So by definition, even in real life, north
always means towards the north pole. If you deviate, then you can't say you're heading north any more! The amount of deviation is quantified by the angle between your actual (deviated) direction and north.
A slight deviation from north could be north-north-east (22.5 degrees deviation), a bigger deviation from north could be north-east (45 degrees deviation), an even bigger deviation from north could be east (90 degrees deviation), and the maximum possible deviation from north would be south (180 degrees deviation).
The point is, none of those deviations can be called north.