I tried asking a question about the fall velocity into a black hole at Can someone adjudicate the conflicting answers to "what is the velocity when falling at the event horizon of a black hole"? and see a similar question at Why can an object not reach the speed of light by falling in a gravitational field with constant acceleration? and Will free-fall object into black hole exceed speed of light $c$ before hitting black hole surface?. I was told that it makes no sense to calculate the velocity as it would be measured by me on Earth, and I couldn't work out the meanings of the other answers. For example, one answer is "you don't actually slow down relative to an outside observer, since the coordinate distance you travel per unit coordinate time (scaled by the metric) is going to c even for the external observer, it's just that the speed c in external coordinates is frozen at the horizon ... The objects freeze because the coordinate time stops, not because their intrinsic velocity is slow." I am afraid I still don't get what I on Earth would consider the velocity to be at the event horizon, nor do I see how I'd figure out how long it takes for something to fall into a black hole by my wrist watch (or even if anything actually falls into a black hole within the age of the universe as I measure the age of the universe). So here is the question asked in another way.
First, picture me at a distance from the sun at Earth's distance, 1.5e11 meters, but not rotating, so that I feel gravitational acceleration (I work it out to .006 m/s2) that I resist with rocket thrusters. Now I drop a rock and it falls to the sun, radius = 6.96e8 meters, but I tie a fishing line to it and let the reel run. The fishing line is magically so little mass as to be ignored (including ignoring its momentum) yet superstrong and 1.5e11 meters long. I work things out so that the rock has an increasing velocity which reaches 616,000 m/s just as it hits the sun, with a reeled out length of line of 1.5e11 - 6.96e8 = 1.493e11 meters. I can convert the speed of the spinning reel to see this velocity. This is all Newtonian, no problem so far.
Now I replace the sun with a black hole of equal mass (radius = 2954 meters). I drop my rock with fishing line, and see no difference for that 1.493e11 meters, reaching 616,000 m/s (0.002c) at that point. Now what happens over the next 6.96e8 meters until the rock reaches the event horizon? Will:
(a) my spinning reel indicate a velocity that climbs up to nearly light speed when the line reeled out equals 1.5e11 meters?
(b) my spinning reel indicate that the rock started slowing down at about 3rs and then comes to a stop just prior to reeling out the full length to the event horizon?
(c) something else?
I really do appreciate your answers and your patience. I think by virtue of this question being asked so often that it is of interest to many people.
