Question

A ball of mass 0.5 us dropped from a height of 5m. What is the greatest velocity it will have right before hitting the ground

Answer 1

The mass of the object is not relevant, unless it is so light, that air resistance will be significant. If we can ignore air resistance, then the speed will depend on gravity (g) and the height (s). The velocity before hitting the ground (v) is given by:
\[v = \sqrt{(2gs)}\]
so
\[v = \sqrt{(2x9.8 x 5)}\]
v=9.9m/s