Searching for simulation software

[theultimate9]

Hello I'm searching for a free or cheap simulation software that can let me make a 3D model of a building and lets me for example test what happens if I roll a ball down the stairs of the building(where the ball reaches at the end and its path).
Also if no such software exist I'd like to know which programming language would help me make this software.
Thank you.

 

[itmoba]

You can tryout Bullet or Physion -- both are good options, and free too!

{*} For more on Bullet, see: https/github.com/bulletphysics/bullet3/releases

{*} For more on Physion, see: http/physion.net