3 canon balls are launched from the edge of a cliff 100 meters above a canyon floor. They are all launched with the same initial speed of 50 m/s but at different angles.

A cannon is located on the edge of a cliff 100 m above a flat, sandy canyon floor. Three cannon balls are launched from the cannon with the same initial speed of 50 m/s, but at different angles. The cannon balls are identical except for their color. A red ball is launched horizontally, a white ball is launched at a 30° angle above the horizontal, and a blue ball

is launched at a 60° angle above the horizontal. In all questions you may ignore air resistance and the length of the cannon, unless otherwise stated.

Which of the three cannon balls hits the ground with the GREATEST kinetic energy?

A. Red

B. White

C. Blue

D. They all hit the ground with the same kinetic

energy.

I understand why the answer is D based on conservation of energy.

KEi + PEi = KEf + PEf

Since KEi is 0 and PEi is the same for all, and PEf is the same for all, then KEf must be equal.

What I don't understand is how this can be since this would mean they all have the same velocity???

Wouldn't the ball that went higher (launched at angle of 60) be moving faster already when it gets back to the initial height and thus be moving faster when it hits the ground? I'm really confused...