Amoving car has momentum. if it moves twice as fast what is it's momentum

as we know that P=mv .. where m is mass and v is velocity ..this relation shows that momentum has a direct relation with  these two quantities .. so when velocity is increased twice 
P' = mv 
P'=m2v
P' = 2 mv here mv is P so
P'=2P 
this shows that momentum will also be doubled by doubling the velocity :)

If there was no gravity then their would be no downword force on the football to have it return the the grownd, and if there was no friction (mainly air friction) then there would be no opposing force the stop the ball from moving through the air allowing the ball to travle ∞.