“The atmosphere slows and oblates all those rocks (meteors).”
That friction from air resistance is what will establish an objects terminal velocity, depending on the objects cross section and “slipperiness” of its surface. Otherwise, gravity would continue to accelerate a falling object.
I wonder what the theoretical maximum speed would be for an object with the optimum needle shape, with the best possible coating? If its incremental drag were less than its incremental gravitational acceleration, it might continue to speed up.
The drag acceleration overcomes the gravitational acceleration as you get deeper into the atmosphere, slowing the object down. The amount it slows is dependent on the drag coefficient, a function of mass and the area and ‘shape’ as seen by the ‘wind stream’.
You are thinking through the problem correctly. Now you have to apply the right numbers. But the bottom line is no rods from god.
I poked at wiki and google on the subject because I don’t understand where people get the notion that it works given the physics. The wiki description talked about starting from orbit at Mach 10, noted that drags slows that down “considerably”, then proceeds to talk about impact energy as if its still traveling at Mach 10. That’s really misleading the general public.
I’ll give you a good analogy to go along with the question/problem. This is actually from personal experience in a way.
I have been a skydiver since the very early 80’s (not so regular any more, but still many thousands of jumps over those years). I was trained in the military and some of those jumps were high altitude jumps from as high as 35,000 ft.
A skydiver face to earth in freefall at 30,000 has a terminal velocity of about 250 mph, depending on size, weight, and how he ‘shapes’ his body in freefall. At 10,000 ft, that same skydiver with same shape, size and weight has a terminal velocity of about 150 mph, and by 2500 ft has a terminal velocity of about 120 mph. (I never clocked myself lower than than, sorry ;) ).
If I was Richard Branson or the red bull guy and I started at 100,000 ft, at 80,000 ft I would be doing about 500 mph but by the time I got to 2500’ I would still be down to 120 mph.
Now a refrigerator in the same scenario might have a terminal velocity at impact of 200 mph, and you might even get a telephone pole up to 400 mph, but that’s nowhere near Mach 10.
Hope this helps.