For ac circuit shown in figure, \( R = 100 \, \text{k}\Omega \) and \( C = 100 \, \text{pF} \) and the phase difference between \( V_m \) and \( (V_B - V_A) \) is \( 90^\circ \). The input signal frequency is \( 10^{x} \, \text{rad/sec} \), where ‘x’ is __________.
