Subject: How can I best investigate velocity versus gravity

For my science fair project this year I'm investigating whether two objects 
 will fall the same speed even if one is hit sideways.  I think the ball 
that is hit sideways will hit first but my dad says to wait until we test 
it.  He says we need to build a test machine that will hit one ball and 
drop the other at the same time.  This seems pretty hard to make.  Are 
there any plans or pictures of test machines that we can copy?  Is there an 
 easier way to test this?  I won third place last year at the science fair 
and I'm hoping I can do better this time.  Thank-you, Mark

Re: How can I best investigate velocity versus gravity