PROJECTILE MOTION-Why isn't there any accelertion in the x direction while there is an acceleration of -g in the y direction?

Question

PROJECTILE  MOTION-Why isn't there any accelertion in the x direction while there is an acceleration of -g in the y direction?

anonymous · Answer

Because there is no force in x direction

hunus · Answer

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The force acting on an object undergoing projectile motion is the force of gravity $$F_{g}=ma$$
which is directed perpendicular to the earths surface. Thus there is no force in the direction parallel to the surface as imranmeah said

anonymous · Answer

because  there is no external force in X direction...F=ma(x) when F(x)=0 then a(x)=0
but in the y direction F(y)=ma(y)  F(y)$$\neq$$0 so a(y)$$\neq$$0 
when there is force we have acceleration when there is not we have no a

anonymous · Answer

As said, because there is no force acting on it in the x/horizontal direction. Think of throwing a ball in a parabolic arc - as soon as you release it, there's no horizontal force acting on it anymore; the only "force" is acceleration due to gravity, as the mass of Earth pulls the ball towards it.