Physics GRE study help---EM
 

im unable to visualize how to solve this one.

1. 1 wire length 2L cross section area=A (XA= cross sectional area from now on) attached to another wire length L, XA=2a. Free end of longer wire at V=8.0 [V] and shorter wire free end at V=1.0 [V]. V @ junction equal to?

do we still neglect edge effects?

I guess EM is my weak point, heres the last EM one

2. Coil turns n=15, r=1cm, w=300rad/s in uniform B field B=0.5T. Assume at t=0 normal N to coil plan in y direction, neglect self inductance. R(coil)=9ohms. whats magnitude of induced current?

Re: Physics GRE study help---EM
 

1). All you need to know is that resistance ought to be proportional to the length of the wire, and inversely proportional to the cross sectional area.

2). Calcuate the change in flux through the area of a single circle of wire per unit time. Multiply by 15. Then you have the EMF. Divide by the resistance, and you have the current.