In load-flow analysis, a voltage-controlled bus is treated as a load bus in subsequent iteration for a _________limit is violated.

The $$rms$$ value of the periodic waveform $$e(t),$$ shown in figure is

The Laplace transformation of f(t) is F(s). Given F(s)=$$\frac\omega{s^2+\omega^2}$$, the final value of f(t) is

The convolution of the function $$f_1\left(t\right)=e^{-2t}\;u\left(t\right)$$ and $$f_2\left(t\right)=e^t\;u\left(t\right)$$ is equal to __________.