First of all, it does not make sense to ask for the magnetic flux ON something. You can have magnetic flux THROUGH something, but not ON it. Make sure you're not supposed to be calculating the magnetic force on the loop.
Second, since you only care about the flux through the second loop due to...
Homework Statement
Inscribe N chords of equal length within a circle of radius r. A body of mass m travels at constant speed v along the chords and is perfectly reflected in each collision with the circle (there is no momentum change tangent to the circle). Show that the radial momentum change...