A wire carries an electric current directed into the page. Then the direction of the magnetic field at point P located as shown in the figure is N W .P E S L х O a d. -Y o b b. +y C. - X O d. +X

A wire carries an electric current directed into the page. Then the direction of the magnetic field at point P located as shown in the figure is N W .P E S L х O a d. -Y o b b. +y C. - X O d. +X

已邀请: