▁easier ▁to ▁observe ▁or ▁measure ▁if ▁the ▁need le ▁is ▁a ▁larger ▁magnet .) ▁Other ▁non - mag net ic ▁materials ▁having ▁elect rical ▁conduct ivity ▁( non - fer r ous ▁met als ▁such ▁as ▁silver , ▁al umin um , ▁or ▁z inc ) ▁also ▁produce ▁the ▁effect . ▁Non - con duct ive ▁non - mag net ic ▁materials ▁( wood , ▁glass , ▁pl astic , ▁ice , ▁etc .) ▁do ▁not ▁produce ▁the ▁effect . ▁ ▁Rel ative ▁motion ▁of ▁the ▁conduct or ▁and ▁the ▁magnet ▁indu ces ▁ed dy ▁curr ents ▁in ▁the ▁conduct or , ▁which ▁produce ▁a ▁force ▁or ▁tor que ▁that ▁oppos es ▁or ▁res ists ▁relative ▁motion , ▁or ▁tries ▁to ▁" cou ple " ▁the ▁objects . ▁The ▁same ▁drag - like ▁force ▁is ▁used ▁in ▁ed dy ▁current ▁bra king ▁and ▁magnetic ▁d amp ing . ▁ ▁See ▁also ▁Far ad ay ▁disc ▁Ind u ction ▁motor ▁History ▁of ▁elect romagnet ic ▁theory ▁ ▁Further ▁reading ▁Walter ▁B aily , ▁A ▁Mode ▁of ▁producing ▁Arag o ' s ▁Rot ation . ▁June ▁ 2 8 , ▁ 1 8 7 9 . ▁( Ph il osoph ical ▁magazine : ▁a ▁journal ▁of ▁theoretical , ▁experimental ▁and ▁applied ▁physics . ▁Taylor ▁& ▁Francis ., ▁ 1 8 7 9 ) ▁ ▁References ▁ ▁External ▁links ▁▁▁ ▁Arag o ' s ▁Rot ations ▁( You Tube ▁video ) ▁ ▁Category : Mag net ism <0x0A> </s> ▁Sa ad at abad ▁( , ▁also