Bhautik Study

Q. A 20cm long metallic rod is rotated with 210 rpm about an axis normal to the rod passing through its one end. The order end of the rod is in contact with a circular metallic ring. A constant and uniform magnetic field of 0.2T parallel to the axis exists
everywhere. The emf developed between the
center and the ring is ________ mV.
Take (π = 22/7)                                                     (JEE-2023)