(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

2. Relevant equations

V = L di/dt

Energy = V*I*t

3. The attempt at a solution

First we find out V across L

This V will be there only for 1st 2 seconds as after that there is no change in current.

So V(across L) is L * di/dt = 2 * 6/2 = 6V equation 1

Now Current is a function of time so it's i = 3t equation 2

So to get Energy we use integration.

Energy = integration of V*I*dt where limits are 0 to 2

So now using equation 1 and 2 we get

Energy = integration of 6 * 3t dt from limits 0 to 2

so this is 18 t^{2}/2 t varies from 0 to 2

So this is 9 (4) = 36 which is not in the options.

Where am I wrong.

I even tried other formula of Energy = 1/2 * L * I^{2}But this gives 24

I'm getting different answer for different formula but neither answer matches options. Where am I wrong?

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# Homework Help: Energy absorbed by the inductor in 4 seconds

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