This is a simulation for three particles with different initial velocity ($$vy_1=v, vy_2=0,vy3=-v$$) under the same gravity $$g=10m/s^2$$

You can drag the initial position of particles as well as initial velocity (drag the tip of velocity arrow--red)

The number of frames per second can be adjusted with a slider. (initial value is fps=5, fps=200 is real time case)

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