When talking about projectile motion, we learned that a bullet fired horizontally falls to the earth with the same velocity as a bullet dropped from your hand. It’s that whole “gravitational acceleration thing” going on – assuming no other force acts in the y axis, the bullet “free falls” back to earth the same as if it were dropped. See the video below for a “Mythbusters” demonstration; and the next time someone says “faster than a speeding bullet…” you can point out, “I assume you are referring to the x component of the bullet’s velocity...”
