Faraday's law – induced emf from changing field

2016 Phase II 1 question

1. 1 Electromagnetic Induction
   A uniform magnetic field is restricted within a region of radius r. The magnetic field changes with time at a rate $\frac{d\vec{B}}{dt}$. Loop 1 of radius R > r encloses the region r and loop 2 of radius R is outside the region of magnetic field as shown in the figure below. Then the e.m.f. generated is:
   
   A $-\frac{d\vec{B}}{dt}\pi R^2$ in loop 1 and zero in loop 2 B $-\frac{d\vec{B}}{dt}\pi r^2$ in loop 1 and zero in loop 2 C Zero in loop 1 and zero in loop 2 D $-\frac{d\vec{B}}{dt}\pi r^2$ in loop 1 and $-\frac{d\vec{B}}{dt}\pi r^2$ in loop 2
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