Coil in a magnetic field problem

Hi,

I was just wondering if someone could work this problem out for me. Here is my link:
http://dl.dropbox.com/u/102096039/Induction%20Problem.JPG

How can I know how far the coil has travelled and hence work out the change of flux, then voltage and current? I was wondering if the induced emf will be less becasue the coil is half way out of the magnetic field? Perhaps half the emf? I am just not sure about this.

Also I was wondering if anyone could tell me which of P=VI or P=I2R I should use for finding the work done?

Any help at all on this problem would be much appreciated!