Electrical – Initial conditions for RLC circuit

passive-networks

circuit

reaches steady-state at \$t = 0^{-} \$, so I am trying to calculate the initial conditions of \$i\$ (current through inductor) and \$v\$ (voltage across capacitor). It is easy to find that \$i(0) = 10A\$, but I am not able to find \$v(0)\$. What am I missing here?

Best Answer

Just think about how you derived the current of 10 amps. There is a 100 volt supply and there is a 10 ohm resistor - to calculate 10 amps it must mean that all the voltage is across the resistor so, what voltage is across the inductor?

Or, put another way, V = L di/dt and, because the circuit is in steady state (your words not mine), this implies the current is also "steady" so, using that formula, what is the voltage across the inductor?