error says UnityEngine.Rigidbody required to access non static member "velocity"

[onionman99]

my question is very simple, i am trying to make my 2d character jump on the y axis but when i try to run the game it says “Assets/jump.js(7,24): BCE0020: An instance of type ‘UnityEngine.Rigidbody’ is required to access non static member ‘velocity’.” i have a rigidbody on my character. do i need to assign a rigidbody in the script? or is it completely different?
my script is very simple, just;

var jump : int = 5;
    
    function Update () {
       if(Input.GetKeyUp("up"))
          {
    	     Rigidbody.velocity = Vector3(0, 5, 0);
    	  }
    }

[Eric5h5]

“Rigidbody” is a class. The Rigidbody component attached to an object is a variable called “rigidbody”. (Technically it’s a property rather than a variable, but the docs call it a variable.)