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=12Bl2ωFor part AO ; eOA=eO−eA=12Bl2ωFor part OC; eOC=eO−eC=12B(3l)2ω∴eA−eC=4 Bl2ω