A current balance is set up so that a mass of 20.0 mg on the upper wire restores balance to the system when a.

Question

current of unknown magnitude is sent though both wires. The wires are 26.5 cm long and have a center-to-center separation of 0.0525 cm.

Find the current...

Answer 1

the force exerted on the two wires is

F=uI^2/(2πd) use MKS

2E-5*9.8=4πE-7*I^2*26.5E-2/(2π*0.0525E-2)
I^2=(2E-5*9.8)*(2π*0.0525E-2)/(4πE-7*26.5E-2)=1.94 A^2

I=1.39 A