For the object launched straight up, the velocity at the top of the path would have been 0m/s.

Suppose it is launched upward at 45 degrees above the horizontal plane, it would have been 141m/s cos 45^{0} = 99.7 m/s.

A projectile is an object upon which the only force acting is gravity. Many projectiles not only undergo a vertical motion, but also undergo a horizontal motion. That is, as they move upward or downward they are also moving horizontally.

There are the two components of the projectile's motion - horizontal and vertical motion. And since perpendicular components of motion are independent of each other, these two components of motion can (and must) be discussed separately.

Conceptual notions about projectiles:

## A projectile is any object upon which the only force is gravity,

## Projectiles travel with a parabolic trajectory due to the influence of gravity,

## There are no horizontal forces acting upon projectiles and thus no horizontal acceleration,

## The horizontal velocity of a projectile is constant (a never changing in value),

## There is a vertical acceleration caused by gravity; its value is 9.8 m/s/s, down,

## The vertical velocity of a projectile changes by 9.8 m/s each second,

## The horizontal motion of a projectile is independent of its vertical motion.

To learn more, see links below:

## Describing Projectiles With Numbers: (Horizontal and Vertical Velocity)

## Characteristics of a Projectile's Trajectory