When making things to small the physics engine is a bit buggy, a 10cm ball will bounce endlessly for instance. When I set that ball to 1m this is solved but now the ball looks like it is falling with a acceleration of 1m/s instead of 10m/s. So I figured to increase gravity, although the ball is now falling a bit more convincingly the impact on other rigid bodies look strange.
So is there a proper way to simulate small stuff like a tennis ball or even a pinball.