In this topic, you study Fleming’s Right Hand Rule.
This empirical rule is very convenient for finding the direction of the induced e.m.f. (or current) in the condition where the conductor is moving at right angles to itself and the field (Fig. 1 a). The rule is as follows:
Fig. 1: Fleming’s right hand rule
Arrange the thumb and the first two fingers of your right hand mutually at right angles to one another. Let the first finger point in the direction of the lines of force (N to S) and the thumb in the direction of motion of the conductor. Then, the second finger will point in the direction the induced e.m.f. (or current).
The rule can be remembered very easily by associating field or flux with the f in first finger, motion of the conductor relative to the field with the m in thumb and current with the c in the second finger. On application of the above rule to the conductor shown in Fig. 1 (a), it will be seen that the induced current is in direction towards the observer.