It is reflected back parallel to the principal axis. (apex)
You mean parallel rays to the principal axis of the concave mirror!
After reflection at the concave surface of the mirror they would get converged at a point on the principal axis of the mirror. This point is known to be the focus.
refracted and then reflected
it moves in a different direction
focus
Focal point of which mirror? Because convex mirror would have a virtual focus which is assumed to be at the back of the mirror.
plane mirror
That passes through the principal focus of the concave mirror
It reflects out through the focus.
It is reflected back parallel to the principal axis. (apex)
It is reflected back parallel to the principal axis. (apex)
It goes to "the point at infinity"
It is called a Cassegrain. The small convex subreflector is a hyperboloid with one focus at the focus of the main mirror, and the other focus just behind the main mirror where the eyepiece is.
focus
true
Focal point of which mirror? Because convex mirror would have a virtual focus which is assumed to be at the back of the mirror.
plane mirror
are you doing your science homework?
That passes through the principal focus of the concave mirror
It reflects out through the focus.
It does not have a specific name.