Maybe too simple is not quite the right category to exclude the question about anti-gravity. If the the problem is simple or not mostly depends on your level of knowledge in physics which can range almost from zero to graduate studies level.
Looking at the question the person asking it writes:
I am thinking of making flying vehicles which is made up of anti-gravity material so that it will not experience any gravity on it and can easily take off and more fuel efficient. Is there any such thing?
So it is implied that some thought went into this, but that is simply not true. Just typing "anti-gravity" into Google or Wikipedia and the first hit is a nice and well written article mentioning that no such material has been found and that there is currently a reward of 1 million US dollars for anybody finding such a material.
So in my opinion it is an abuse of this site to ask questions where it is obvious that no own thought or effort went into it at all. This is similar to the current disapproval of homework-like questions without any own effort. The physics part of stackexchange is in this aspect not so different to the other stackexchange sites. A question like "I am thinking of creating my own OS but have trouble finding a processor which has a Ruby compiler builtin, is there a workaround?" would certainly be downvoted or deleted because it clearly shows that you did not read anything at all about an operating system.
It could be added to the FAQ of this site that question with show no own research effort will be closed.