If you’re postulating anything like most people’s ideas of Superman, you’re already saying “ignore conservation of momentum”, because inherent in the concept is that he flies around in arbitrary ways without having to push on anything. In other words, by the way you phrased the problem, you just asked the student to ignore the very thing you’re asking the problem about. This won’t turn out well.
(Response to old post.)
If you’re postulating anything like most people’s ideas of Superman, you’re already saying “ignore conservation of momentum”, because inherent in the concept is that he flies around in arbitrary ways without having to push on anything. In other words, by the way you phrased the problem, you just asked the student to ignore the very thing you’re asking the problem about. This won’t turn out well.