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LESSON NOTES:

Fleming’s Right Hand rule
Stretch the thumb, forefinger and middle finger of right hand so that they are
perpendicular to each other. If the forefinger indicates the direction of the magnetic field
and the thumb shows the direction of motion of conductor, then the middle finger will
show the direction of induced current

Electric Generator
It is a device which converts mechanical energy into electrical energy. It is based on
electromagnetic induction principle as explained above.

Working of electric Generator
a. When the coil ABCD is rotated clockwise . By applying Fleming’s right-hand rule, the
induced currents are set up in these arms along the directions AB and CD. Thus an
induced current flows in the direction ABCD. This means that the current in the external
circuit flows from B2 to B1.
b. After half a rotation, arm CD starts moving up and AB moving down. As a result, the
directions of the induced currents in both the arms change, giving rise to the net
induced current in the direction DCBA. The current in the external circuit now flows from
B1 to B2. Thus after every half rotation the polarity of the current in the respective arms