The switch ( S ) closes at $t=0 \mathrm{sec}$. The time, in sec the capacitor takes to charge to 50 V is __________ . (Round off to one decimal places)

The circuit shown in the figure is initially in the steady state with the switch K in open condition and $$\overline K $$ in closed condition. The switch K is closed and $$\overline K $$ is opened simultaneously at the instant $$t=t_1$$, where $$t_1 > 0$$. The minimum value of $$t_1$$ in milliseconds, such that there is no transient in the voltage across the 100 $$\mu$$F capacitor, is ___________ (Round off to 2 decimal places).

A 100 Hz square wave, switching between 0 V and 5 V, is applied to a CR high-pass filter circuit as shown. The output voltage waveform across the resistor is 6.2 V peak-to-peak. If the resistance R is 820 Ω, then the value C is ______ μF.

(Round off to 2 decimal places)

A resistor and a capacitor are connected in series to a 10 V dc supply through a switch. The switch is closed at t = 0, and the capacitor voltage is found to cross 0 V at t = 0.4τ, where τ is the circuit time constant. The absolute value of percentage change required in the initial capacitor voltage if the zero crossing has to happen at t = 0.2τ is _______  (rounded off to 2 decimal places).