(2011?Foshan) As shown in the figure, the N pole of the bar magnet and the C end of the energized solenoid are attracted to each other, please mark the magnetic poles of the energized solenoid and the

(2011?Foshan) As shown in the figure, the N pole of the bar magnet and the C end of the energized solenoid are attracted to each other, please mark the magnetic poles of the energized solenoid and the positive and negative of the power supply. The N pole of the bar magnet is attracted to the right end of the solenoid, and the heteronymous magnetic poles are attracted to each other, so the right end of the solenoid is the S pole, and the left end is the N pole;

When a small magnetic needle is placed at point A, the NS pole of the small magnetic needle is attracted to each other with the NS pole of the solenoid, and the NS poles of the solenoid are attracted to each other when the small magnetic needle is stationary, and the mutually approaching poles must be the heteronymous magnetic poles, i.e., the N pole of the small magnetic needle is close to the right end of the solenoid, and the S pole of the small magnetic needle is close to the left end of the solenoid. S pole near the left end of the solenoid N pole. As shown in the figure: