A conducting rod AC of length 4l is rotated about a point O in a uniform magnetic field B→ directed into the paper. AO = l and OC = 3l. Then
VA-VO=Bωl22
VO-VC=72Bωl2
VA-VC=4Bωl2
VC-VO=92Bωl2
By using, e=12Bl2ω
For part AO ; eOA=eO-eA=12Bl2ω
For part OC; eOC=eO-eC=12B(3l)2ω
∴eA-eC=4Bl2ω