Time limited actions

Hi, trying to make a power-up that allows the character to float for a limited amount of time. Got the float figured out and how to control the gravity from the 3rd Person Platformer tutorial. What I need now is to figure out how to make it so they player can only float for a limited amount of time, say 1 second before gravity takes effect as normal again.

Something like this should work. You haven't said how you're activating the power up (a button press, some sort of trigger object etc) so I haven't included a method for calling the GravityChange function. I'll leave that to you.

var useGrav : boolean = true;

    function Update ()
    {
    rigidbody.useGravity = useGrav;

    GravityChange ();

    }

    function GravityChange()
    {
    useGrav = false;
    yield WaitForSeconds (1);
    useGrav = true;
    }