Rotating an object according to the force.

I am working on a project now which is about moving a paperboat forth and back. I have applied force to the object which will let the object move just by clicking on a plane. I want the object to spin according to the force too. The object is not rotating at all. Please help me in fixing this problem. My code is...

var strength : float = 10.0f;

var amount: float = 0.0f;

var smooth = 2.0;

var tiltAngle = 30.0;

function Update () 



        var ray = Camera.main.ScreenPointToRay(Input.mousePosition);

        var hit : RaycastHit;

        if (Physics.Raycast(ray, hit)) 

            var delta = transform.position - hit.point ;

            rigidbody.AddForce(delta.normalized * strength, ForceMode.Impulse);
            rigidbody.AddTorque (0, 10, 0);

Please respond to this question as soon as possible. Thank you...

Forces using the physics engine need to be added inside FixedUpdate() instead of Update() Try that and see if it works.

Here's a link to a post about how to use slerp to look at a target point.

Here's a link to an answer on this forum that deals with limiting slerp rotation to one axis. See if this helps.