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DB
Dec16-04, 05:34 PM
If gravity aplies the same force on every object, accellerating it to about 10 m/s2 (gee), then how come for example helium floats up to the sky?

Thnx

ZapperZ
Dec16-04, 05:42 PM
If gravity aplies the same force on every object, accellerating it to about 10 m/s2 (gee), then how come for example helium floats up to the sky?

Thnx

Hint: the helium balloon will NOT float up the sky if it is in a vacuum, or very thin air.

Zz.

HallsofIvy
Dec16-04, 06:51 PM
Because it is "in the sky"- in other words, in air that has a higher density than helium has. The air is attracted by a greater force than the helium is (gravitational force is proportional to the mass) and "pushes" the helium up.

Gokul43201
Dec16-04, 07:04 PM
If gravity aplies the same force on every object, accellerating it to about 10 m/s2 (gee), then how come for example helium floats up to the sky?

Thnx

Hope this isn't too many cooks...

Try this : If gravity applies the same force on every object, accellerating it to about 10 m/s2 (gee), then how come for example wood floats up to the top of a lake ?

NOTE : Gravity does not apply the same force on all objects, it creates the same field (at some height)...but that's not important here.