Flash CS3 [as2]. Gravity

Hi,

I’m moving the movieclip from left to right direction, I want to set gravity for that movieclip. Depending upon the gravity, the direction of the movieclip should also change. Plz find the link below.

http://www.officegamespot.com/officegames/appleshooter.htm

yes I want to do the same as arrow.

Plz help me.

Thanks in advance.
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