When we talk about projectile motion, it involves understanding both horizontal and vertical components of movement separately.
In our exercise example, child 1's snowball thrown horizontally initially moves due to the force applied by the throw. Meanwhile, child 2's snowball initially moves downward purely due to gravity.
- The horizontal motion of the snowball is not affected by gravity until it eventually hits the ground. This means the snowball will travel with a constant horizontal velocity (ignoring air resistance).
- The vertical motion, however, is influenced by gravitational acceleration, causing the snowball to accelerate downwards at 9.81 m/s².
In essence, whether thrown straight or horizontally, the vertical motion of the snowball is constituted equally by gravity, leading us to recognize why both snowballs accelerate downward at the same rate.