Sphere Falling through floor

Questions & Answers
1

I have been posting this question for awhile and havnt gotten an answer. My sphere keeps falling through the floor. It is suposed to be the character. I just want it to move i have a cube as a platform and it has a box collider. My sphere which is the character has the character controller a sphere collider and the script which is

var speed = 3.0;
var rotateSpeed = 3.0;

function Update ()
{
var controller : CharacterController = GetComponent(CharacterController);

// Rotate around y - axis
transform.Rotate(0, Input.GetAxis ("Horizontal") * rotateSpeed, 0);

// Move forward / backward
var forward = transform.TransformDirection(Vector3.forward);
var curSpeed = speed * Input.GetAxis ("Vertical");
controller.SimpleMove(forward * curSpeed);

}

@script RequireComponent(CharacterController)

If anyone sees anything wrong with the script or anything wrong with my components on the objects please tell me

2

try adding rigidbody to sphere