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- Homework Statement
- At the beginning the switch c of the circuit is in position 1. At t=0, it switches to position 2.

(1) Find ##I(0).## (2) Find ##t*## such that ##I(t*)=35mA.##

- Relevant Equations
- ##I(t)=I(0)(1-e^{(-R/L)t)},\ I(0)=\frac{V}{R}##

What I have done:

(1) ##I(0)=\frac{V}{R}=\frac{1.5}{25}A=0.06 A.##

(2) By setting ##I(t*)=0.06(1-e^{-(35/0.4)t*})=35 mA## we get ##t*\approx 0.01 s##

What I have done seems correct to me, but the result for part (2) should be different.

I would be grateful if someone could point out to me where I have made a mistake.

(1) ##I(0)=\frac{V}{R}=\frac{1.5}{25}A=0.06 A.##

(2) By setting ##I(t*)=0.06(1-e^{-(35/0.4)t*})=35 mA## we get ##t*\approx 0.01 s##

What I have done seems correct to me, but the result for part (2) should be different.

I would be grateful if someone could point out to me where I have made a mistake.

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