A cannon shoots a projectile horizontally from a 24 m high cliff. The cannon ball lands 100m from the base of the cliff. a. With what velocity is the projectile fired?
b. What is the projectile's velocity as it strikes the ground?

an obstruction

less than one you can't create energy

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.