The horizontal velocity is constant ( air friction modifies it slightly but you specified a vacuum ) as long as the ball flies.
12.
After a destructive battle, the villain was finally defeated when he boasted how he used a chemical coating to protect himself from air friction.
13.
If there's a speed at which a volleyball in air would burn from air friction, I doubt you could get there by hitting it.
14.
The more efficient rocket plume geometry and the reduced air friction allows the engine to be 5 % more efficient per amount of fuel burned.
15.
So that jet pilots could endure the heat generated by air friction at supersonic speeds, a way had to be found to cool their cockpits.
16.
There are other kinds of frictions, such as air friction or " drag " ( see fluid friction ) that aren't modelized in the same way.
17.
The sleek trains, distinguished by a protruding snout that decreases air friction, commonly run at speeds of up to 240 kilometers per hour ( 150 mph ).
18.
:: Shells don't really follow a parabolic path; that's a simplification based on ( 1 ) ignoring air friction and ( 2 ) treating the Earth as flat.
19.
So am I right in concluding that reducing air friction is the only reason for withdrawing the wheels ?-- Wikicheng 09 : 05, 16 June 2006 ( UTC)
20.
As long as the object is not slowed by collision or by air friction, its direction doesn't affect whether it will escape or not, only its speed does.
