Here's why:
* Gravity: The primary force acting on a projectile is gravity, which constantly pulls it downwards.
* Vertical Motion: As the projectile travels upwards, gravity slows it down until it momentarily stops at the highest point.
* Instantaneous Velocity: At this peak, the projectile's vertical velocity is zero. It's not moving upwards or downwards for that brief instant.
Important Note: While the vertical velocity is zero at the highest point, the projectile still has horizontal velocity. This means it continues moving horizontally at a constant speed.
