Can a particular shape of magnet be able to apply patent? Thanks.

Your question, as best understood, is whether a different shape of a magnet for a motor would comprise a patentable invention.   An inventor is entitled to a patent for their invention if the invention is useful, new and non-obvious.   While an electric motor is certainly useful, an electric motor using a differently shaped magnet will be useful only if it works as an electric motor.   The motor invention is new if the shape of the magnet has not been used before its invention by the inventor and has not been disclosed or used in public by the inventor more than one year prior to the inventor's filing the patent application.   The motor invention is non-obvious if a person of ordinary skill in the art of constructing electric motors, having before them all the art prior to the invention of the new motor, would not find the construction of the new motor obvious. The patentability of such an invention is a mixed question of law and fact.  I recommend you consult with a registered patent professional (either a patent attorney or a patent agent) for a professional opinion as to the patentability of a motor with the particularly shaped magnet.  Note that a registration to practice patent law before the U.S. Patent and Trademark Office is a nationwide license and that you may consult a registered patent professional anywhere for the needed opinion.