As shown in the figure, the metal bar PQ moves to the left () A. When the rod is moving at a constant speed, the potential difference between a and B is not equal to zero. B. when the rod is accelerating, the current direction in coil N changes from a through n to B. C. when the rod is accelerating at a constant speed, there may be C → D current in bulb D. when the rod is decelerating, there may not be C → D current in bulb L

As shown in the figure, the metal bar PQ moves to the left () A. When the rod is moving at a constant speed, the potential difference between a and B is not equal to zero. B. when the rod is accelerating, the current direction in coil N changes from a through n to B. C. when the rod is accelerating at a constant speed, there may be C → D current in bulb D. when the rod is decelerating, there may not be C → D current in bulb L

A. When the rod moves at a constant speed, the electromotive force generated by PQ remains unchanged, the magnetic flux through the transformer auxiliary coil remains unchanged, the auxiliary coil does not produce induced electromotive force, the potential difference between a and B points is equal to zero, so a is wrong; B. when the rod accelerates, according to the right-hand rule, the current flowing through PQ flows from P to Q, according to e = BLV, induction