Can anybody help with the attached exercise?
The answers are R=750 ohms, C=200 micro F, L=25H
To get R I tried Vc(t)/Il(t) but couldn't get 750 ohms.
To find C I have used the following equation.
\(\begin{array}{l}
{v_c} = \frac{1}{c}\int_0^t i \,dt \\
\to 30 - 10{e^{ - 20t}} + 30{e^{ - 10t}} = \frac{1}{1000c}\int_0^t {40{e^{ - 20t}} - 60{e^{ - 10t}}\,dt} \\
\end{array}\)
It comes close to 200 micro F but not equal.
I am not sure how to get L
The answers are R=750 ohms, C=200 micro F, L=25H
To get R I tried Vc(t)/Il(t) but couldn't get 750 ohms.
To find C I have used the following equation.
\(\begin{array}{l}
{v_c} = \frac{1}{c}\int_0^t i \,dt \\
\to 30 - 10{e^{ - 20t}} + 30{e^{ - 10t}} = \frac{1}{1000c}\int_0^t {40{e^{ - 20t}} - 60{e^{ - 10t}}\,dt} \\
\end{array}\)
It comes close to 200 micro F but not equal.
I am not sure how to get L
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