Items falling through floor?

Placed sphere, added FPS script. Press play, fall through floor. ???

go to sphere, components, physics, rigidbody, check "use gravity" and it should work. also, try what "joe" and "adam" said those were good answers also.

floor and sphere must have a collider component. add rigidbody component to sphere + check gravity flag. mesh collider against mesh collider will not work either.