The present research paper derives a formula for gravitational force acting between the black hole and light particle passing near the radius of event horizon of black holes and calculates also their values of different test black holes existing in only X-ray binaries (XRBs).

In this research paper, we have used the formula for gravitational force acting between the black hole and light particle passing near the radius of event horizon of black holes (Mahto et al. 2013) to calculate their values for different test of black holes existing in Active Galactic Nuclei (AGN) and compared with that of the black holes in XRBs.