Components of Projectile Motion

* Horizontal Velocity (Vx): This component remains constant throughout the flight.

* Vertical Velocity (Vy): This component changes due to gravity.

Why Horizontal Velocity Remains Constant

* Neglecting Air Resistance: In ideal projectile motion, we assume no air resistance. This means there's no force acting horizontally on the projectile.

* Newton's First Law: Since there's no horizontal force, the projectile continues to move horizontally at a constant velocity according to Newton's First Law of Motion (an object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force).

Why Vertical Velocity Changes

* Gravity: The primary force acting on a projectile is gravity. Gravity pulls the object downwards, constantly changing its vertical velocity.

* Acceleration Due to Gravity (g): The acceleration due to gravity is approximately 9.8 m/s². This means the vertical velocity of a projectile increases by 9.8 m/s every second it's in the air.

Summary

The horizontal component of a projectile's velocity remains constant because there is no horizontal force acting on it (ignoring air resistance). The vertical component changes because gravity constantly accelerates the projectile downwards.