[JJJ]

Does anyone know if basketballs bounce and move through the air differently at higher altitudes? I ask because I used to live at close to 4K altitude and played tennis, and a tennis ball bounces noticeably differently at high altitude compared to sea level.

The bounce of a basketball at any altitude should be the same if it is filled to the same measured (relative) pressure at that altitude (which presumably they are). The bounce depends on the difference between the internal and external pressures, which is what an ordinary pump measures (as opposed to measuring absolute internal pressure). The issue with tennis balls arises because they are filled by the manufacturer to a specific pressure near sea level, then brought to higher altitude where their pressure relative to external pressure is higher (because external pressure is lower). As a result, they bounce a lot higher. That is why you can buy specially designated high-altitude tennis balls that are filled initially by the manufacturer to a lower pressure (relative to sea level).

Higher altitude should affect the air friction experienced by a shot basketball, but I do not know whether this effect is large enough to be noticeable.

(for completeness, the acceleration of gravity is slightly lower in Boulder than at sea level, but the difference is negligible)

And this is why the CARDboard is so awesome. Learn something new every day!

[JJJ]

Does anyone know if basketballs bounce and move through the air differently at higher altitudes? I ask because I used to live at close to 4K altitude and played tennis, and a tennis ball bounces noticeably differently at high altitude compared to sea level.

The bounce of a basketball at any altitude should be the same if it is filled to the same measured (relative) pressure at that altitude (which presumably they are). The bounce depends on the difference between the internal and external pressures, which is what an ordinary pump measures (as opposed to measuring absolute internal pressure). The issue with tennis balls arises because they are filled by the manufacturer to a specific pressure near sea level, then brought to higher altitude where their pressure relative to external pressure is higher (because external pressure is lower). As a result, they bounce a lot higher. That is why you can buy specially designated high-altitude tennis balls that are filled initially by the manufacturer to a lower pressure (relative to sea level).

Higher altitude should affect the air friction experienced by a shot basketball, but I do not know whether this effect is large enough to be noticeable.

(for completeness, the acceleration of gravity is slightly lower in Boulder than at sea level, but the difference is negligible)

And this is why the CARDboard is so awesome. Learn something new every day!