Momentum of Rigid Bodies with Different Masses

Hi. Back in Blender 2.82 after a long absence from the Blender world.

I’m doing a little physics experiment with rigid body objects of different masses to see how well momentum works in the physics engine. I have 4 objects ( 2 cubes at 1kg and 1000kg, 2 spheres at 1kg and 1000kg).

I let the animation system moved them in the X axis using keyframes 1 and 30 to build up a velocity then at frame 31 the animation is disabled to let the Dynamics take over.

Yes all objects carry on moving after frame 31 but what I can’t figure out is why the 1kg and 1000kg cubes (and for that the spheres) finish up at the same distance.

I would have expected the 1000kg objects to stop well before the 1kg because of it’s mass. All active and passive objects have the default friction setting of 0.5.

I’ve increased the “Steps per Second” and “Solver Iterations” in Rigid Body World settings to no avail.

Can anyone explain what I see and how to resolve it or did I forget something from my high school physics classes? :grinning:


Well it seems I did forget my high school physics in regards to force and momentum :man_scientist:

I understand now what I see happening in Blender.