Without air resistance, every falling object has 9.8 m/s² of acceleration, from the instant it starts falling until it hits the bottom.
None of these things makes any difference:
-- whether you throw the object up, throw it down, or just drop it -- any horizontal speed it has -- how much mass the object has -- how heavy it is -- what color the object is -- how far it falls -- how long it takes.
The troposphere starts at the Earth's surface and extends 8 to 14.5 kilometers high (5 to 9 miles). This part of the atmosphere is the most dense. Almost all weather is in this region.
