A coil with 347 turns of wire, a total resistance
of 49 Ω, and a cross-sectional area of 0.28 m2
is positioned with its plane perpendicular to
the field of a powerful electromagnet.
What average current is induced in the coil
during the 0.31 s that the magnetic field drops
from 2.4 T to 0.0 T?
Answer in units of A
cosα=1,
ℇ=ΔΦ/Δt = N•Δ(B•Acosα)/Δt=
=N•A•ΔB/Δt,
ℇ=I•R,
N•A•ΔB/Δt= I•R,
I= N•A•ΔB/Δt•R=
=347•0.28•2.4/0.31•49 = 15.35 A