We know,  1 m  =1000 mm and 1 cm =10 cm Diameter of the copper Rod =2 cm Radius of the copper rod =r=1 cm Length of the Rod =h=10 cm Length of the wire =h=10 m =1000 cm Let suppose the radius of the wire =RFrom the statement: Volume of the rod = volume of the wire  π r2h= π R2H1×1×10=1000×R2 or R=101​ cm or 0.1 cm Diameter of the wire =2r=2×0.1=0.2 cm Therefore,the thickness of the wire is 0.2 cm or 2 mm.