A circuit is set up consisting of three resistors combined in different ways, with no battery or power supply attached, but with a uniform magnetic field pointing up out of

the plane of the circuit in a small w by l region, as shown below. a) Determine an expression for the effective resistance of the circuit. (3 marks) b) What value of R1 would make the effective resistance of the circuit equal to R3? Conceptually explain why this works. (2 marks) c) If we power the circuit by making the B field decrease by 2T every second and for l = 0.03 m and w =0.02 m we obtain a current of 2A, what is the effective resistance of the circuit? Also, in what direction does the current flow? (5 marks)