e=dtdϕ=dtd(Bπr2)=2πrBdtdr=2×π×2×10−2×4×10−2×2×10−3=3.2×10−6πVol=3.2πμV
A conducting circular loop is placed in a uniform magnetic field 0.04 T with its plane perpendicular to the magnetic field. The radius of the loop starts shrinking at 2 mm/s. The induced emf in the loop when the redius is 2 cm is :
Held on 30 Apr 2009 · Verified 9 Jul 2026.
1.6πμv
3.2πμv
4.8πμv
0.8πμv
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