You can put this solution on YOUR website! i=io e^(-Rt/L)
i=0.1
io=4
R=150
L=0.012
Solve for t
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0.1 = 4*e^(-150t/0.012)
0.025 = e^(-12500t)
-12500t = ln(0.025)
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-12500t = -3.688879
t = 2.951104x10^-4
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Cheers,
Stan H.
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