Given: No. of turns N=1000 Face area, A=4 cm2=4×10−4 m2 Change in magnetic field, ΔB=10−2wbm−2 Time taken, t=0.01 s=10−2sec Emf induced in the coil e= ? Applying formula, Induced emf, e=dt−dϕ =N(ΔtΔB)Acosθ=10−21000×10−2×4×10−4=400mV
A coil of circular cross-section having 1000 turns and 4 cm2 face area is placed with its axis parallel to a magnetic field which decreases by 10−2 Wb m−2 in 0.01 s. The e.m.f. induced in the coil is:
Held on 11 Apr 2014 · Verified 6 Jul 2026.
400mV
200mV
4mV
0.4mV
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