A rotating armature of a simple generator consists of a loop ABCD to which connections are made through sliding contacts.The armature is rotated at 1500 rpm in the magnetic field `(vec B )` of` 0.5 N//A.m`. Determine the induced emf between the terminals P and Q of the generator at the instant shown in the adjoining figure.

A metal rod of length 1 m is rotated about one of its endsin a plane at right anglesto a uniform magnetic field of induction 2.5 xx 10^-3Wb//m^2 . If it makes 1800 r.p.m. calculate the induced emf between it.

A 1.0 m long metallic rod is rotated with an angular frequency of 400 rad s ^-1 about an axis normal to the rod passing through its one end. The other end of the rod is in contact with a circular metallic ring .A constant and uniform magnetic field of 0.5 T parallel to the axis exists eveywhere. Calculate the emf developed between the centre and the ring