a. It represents Fleming's right hand ruleused for finding the direction of induced current with respect to the directions of the magnetic field and motion of the conductor.
The direction of current induced in a conductor can be obtained by holding the thumb, the index finger, and the middle finger of your right hand mutually perpendicular to each other. In this situation, the thumb indicates the direction of the motion of the conductor, the index finger points along the magnetic field, and the middle finger points along the current induced in the conductor.
b. It represents Fleming's left hand rule used for finding the direction of magnetic force when a current carrying conductor is placed in a magnetic field.
This rule states that if you stretch the thumb, index finger, and middle finger of your left hand such that they are mutually perpendicular to each other, then your index finger represents the direction of the field, the middle finger represents the direction of the current, and the thumb represents the direction of the force experienced by the conductor.
