Assuming i know the velocity (m/s), how do i convert this to density(Kg/m^3)?

Question

Assuming i know the velocity (m/s), how do i convert this to density(Kg/m^3)?

Answer 1

if you know mass and velocity, you can calc. energy/force...

Answer 2

There's no such conversion.  For instance, a gold brick and a Nerf ball could have the same velocity, but different densities.