In the Left-Hand Rule for Generators, which finger indicates the current induced into the armature?

In the Left-Hand Rule for Generators, which finger indicates the current induced into the armature?

• A. Thumb
• B. Center (middle) finger
• C. Index finger
• D. Little finger

Answer: (B)

In Fleming’s left-hand rule for generators, three perpendicular directions link motion, magnetic field, and induced current. Hold the left hand so that the thumb points in the direction of the conductor’s motion, the forefinger points from the magnetic field’s N to S, and then the middle finger points in the direction of the induced current into the armature. So the middle finger indicates the current. This setup keeps the three directions distinct and consistent: changing the motion or the field changes where the middle finger points, i.e., the current direction.

In Fleming’s left-hand rule for generators, three perpendicular directions link motion, magnetic field, and induced current. Hold the left hand so that the thumb points in the direction of the conductor’s motion, the forefinger points from the magnetic field’s N to S, and then the middle finger points in the direction of the induced current into the armature. So the middle finger indicates the current. This setup keeps the three directions distinct and consistent: changing the motion or the field changes where the middle finger points, i.e., the current direction.