Question

Three parallel wires (A, B, C) each of length 35 cm lie flat on a table with wire B between wires A and C. Wire B is 15 cm from wire A. Wire C is 30 cm from wire B (so it is 45 cm from wire A). The current in wire A is 30 A, the current in wire B is 10 A, and the current in wire C is 90 A. Wires A and B have current in the same direction as each other, but wire C has current in the opposite direction. Rank the wires by the net magnetic force exerted on it, largest net force to smallest. 

• C,B,A 

• A,B,C 

• B,C=A 

• С,А,В 

• A=B=C

Answer 1

Answer 2

Net Magnetic field on a B с BBC </ do IB 2л (6xte-2) & Molc 25 (+6xto-2) 46A [ 1 - 2 7 27 Hi5cm tzoumy 0.45 ] - Иә (-132, 33) R T 2 Net magnetic field on B BAC г.) do IA 2ліѕ хір-2) CÊ fcholc 2a(20x-2) Mo T न (-5oo) on Net magnetic field Вар До І. 2л (4sxno-?) -) м.Ів c-k) әл (30xo 2) - М. (-Тоо) к т 27

133.33 Force on A , FA = IA TX BBC 3 x 35 5 x 4 (see) (*) a 1 399.965 - 5250 Mo 2 N añ Force on B, FBE IBIX BA 10 x [0.35 (H) x Mo (500) (-k)] 2n che hanno -1750 Mo (E) N Force onc, = Ic TX BAB = 90 x(0.35(453x do 800(-k)] 3150 Mo ( Î ) N 25 A Pel > IFIBRIFIA CBA (First option)