A projectile is an object fired or thrown by force. Play with the sliders to see how a projectile moves:
When drag is zero the projectile's path is a parabola.Try different angles, which angle takes the projectile furthest along? So what angle should you throw at if you want a ball to go far away?
Can you hit the same spot using different power/angle combinations?
A moving projectile gets slowed down by the air (or water etc) that it moves through. This is called "drag", and is actually a complicated subject.
Here we just use the simple approximation that drag is proportional to the square of the velocity.