The reflection property of which conic is used in radio direction finding and in the construction of mirrors inside telescopes?
Reflecting property of hyperbolae :
A beam of light is directed at one of the foci (with the curve "between" the source and the focus) then it will be reflected by the curve through the other focus!
This property of the hyperbola has applications!
It is used in radio direction finding (since the difference in signals from two towers is constant along hyperbolae), and in the construction of mirrors inside telescopes (to reflect light coming from the parabolic mirror to the eyepiece).