What is the ratio of orbital velocity to escape velocity

Orbital velocity is the velocity of celestial body/satellite revolving around another celestial body in circular orbit. 
V =  ---(i)

Escape velocity is the minimum initial velocity a body should be given to escape it from gravitational field.
V =  ---- (ii)

Divide (i) and (ii)



R = radius of circular orbit, M = mass of the celestial body about which satellite/body is performing circular motion. G = Universal gravitational constant 

Lexy is correct because angle r is between the incident wave,  n  = 0, and a diffracted wave.