The questions I need help with are in bold
The time constant of an RC circuit is given by Hence if capacitance is fixed, the time constant can be varied by varying thr resistance value.
While discharging the capacitor, The voltage V is given by
Hence V(0) =V0. . After a long time, t=infinity, V(infinity)=0 .
t1/20 says that the capacitor is discharged 1/20 of its initial voltage.
Hence On solving this, we get,
Yes if time constant increases, t1/20 increases by a factor of ln(20)=3
Similarly, for t1/2 , . Hence on rearranging this like in the above expression, we get .
at t>=5 time constants, the value of voltage approaches almost zero. Hence at t=20 time constants, The voltage across the capacitor is decayed mostlly and can be approximated to zero. Hence the ratio will also be zero.
The questions I need help with are in bold [Resistance-Capacitance] = [Resistance] middot [Capacitance] = volta/amp...
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