Question

the left side of the armature in an electric motor is pushed down. when the current changes direction, how is the motion of the armature affected? it is pulled up on the left side it is pulled up on the right side it is pulled toward the commutator it is pushed away from the commutator

Explanation:

In an electric motor, the force on the armature (a current - carrying conductor in a magnetic field) is given by the motor effect, \( \vec{F}=I\vec{l}\times\vec{B} \) (where \( I \) is current, \( \vec{l} \) is the vector representing the length and direction of the conductor, and \( \vec{B} \) is the magnetic field). The direction of the force depends on the direction of the current and the magnetic field. When the current changes direction, the direction of the force on the armature also changes. Initially, the left side of the armature is pushed down. When the current direction reverses, the force on the left side will be in the opposite direction, so it will be pulled up on the left side.

Answer:

It is pulled up on the left side