Real life phenomenon of nuclear physics

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be

f is prop to m1xm2 double m1 double force

i will answer your question if you answer mine

3. dark matter

empty space could also be a simple vacuum