A electric circuit is made of a resistance, a solenoid and a power source.(adsbygoogle = window.adsbygoogle || []).push({});

Resistance, V= Ri

Solenoid, V = L (di/dt)

Power source, tension E(t)

Hence, L(di/dt)+ Ri = E(t). If E(t)= 20sin(5t), if L= 4 henrys and R= 20 ohms. If the intensity equals 0 at the beginning, find the amperage of i(t). Show that after a certain amount of time, the electric current becomes stationary.

I would really need help to start this problem, I'm completly lost . i was stuck at 20sin(5t)= 4(di/dt) + 20i... The answer is supposed to be

i(t)= 1/2( sin(5t)-cos(5t) +e^-5t)

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# Homework Help: Calculus problem (electric circuit)

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