The origin of the most probable 3:2 twin-peak quasi-periodic oscillations (QPOs) frequency ratio in the micro-quasars

► The accretion disk oscillations excites QPOs in the X-ray fluxes. ► The shocks may possibly be excite the oscillations in the accretion disk. ► We find the vertical to radial oscillation frequencies ratios are close to the 3:2. ► We determine the shock location in terms of flow parameters and black hole spin. ► We also estimate the possible spin of a few Galactic Micro-quasars from their QPOs.