▁south ▁pol es ▁on ▁neighbor ing ▁g ears ▁act ▁like ▁the ▁teeth ▁and ▁tr ough ▁of ▁neighbor ing ▁sp ur ▁g ears , ▁as ▁each ▁g ear ▁drives ▁the ▁next ▁g ear ▁in ▁the ▁chain . ▁Such ▁magnetic ▁g ears , ▁like ▁sp ur ▁g ears , ▁always ▁have ▁g ear ▁r ati os ▁as ▁the ▁r ati os ▁of ▁small ▁integers . ▁ ▁More ▁s oph istic ated ▁magnetic ▁g ear ing ▁uses ▁pole ▁pieces ▁to ▁mod ulate ▁the ▁magnetic ▁field ; ▁they ▁can ▁be ▁designed ▁to ▁have ▁g ear ▁r ati os ▁from ▁ 1 . 0 1 : 1 ▁to ▁ 1 0 0 0 : 1 . ▁ ▁See ▁also ▁ ▁Elect romagnet ic ▁cl utch ▁ ▁Mag net ic ▁particle ▁cl utch ▁ ▁References ▁ ▁Category : Mag net ic ▁devices ▁Category : Rot ating ▁sh aft ▁cou pl ings <0x0A> </s> ▁Re ka ▁is ▁a ▁village ▁in ▁Cro atia . ▁It ▁is ▁connected ▁by ▁the ▁D 4 1 ▁highway . ▁ ▁References ▁ ▁Category : Pop ulated ▁places ▁in ▁Kop riv nica - K ri ž ev ci ▁County <0x0A> </s> ▁The ▁B TB ▁E 2 E , ▁also ▁known ▁as ▁F ▁ 2 / 2 ▁and ▁De ▁ 2 / 2 , ▁were ▁a ▁pair ▁of ▁Swiss ▁electric ▁locomot ives ▁operated ▁by ▁Burg dorf ▁Th un ▁Bahn ▁( B TB ) ▁in ▁the ▁early ▁tw enti eth ▁century . ▁ ▁They ▁are ▁the ▁oldest ▁three ▁phase ▁locomot ives ▁designed ▁for ▁full ▁service ▁operation ▁that ▁have ▁been