I have the following error - Assets/Jumping.cs(19,29): error CS0120: An object reference is required to access non-static member `UnityEngine.Rigidbody2D.AddForce(UnityEngine.Vector2, UnityEngine.ForceMode2D)'.

I’m coding a 2D game where i need my character to jump I’ve made this code but i keep getting this error.

using UnityEngine;
using System.Collections;

public class Jumping : MonoBehaviour {

private int jumpHeight = 50;
// Use this for initialization
void Start () {

}

// Update is called once per frame
void Update () {
	if (Input.GetButtonDown("Jump") || Input.GetKey ("w")) {
		playerJump();
	}
}
void playerJump(){
	Rigidbody2D.AddForce(new Vector3(0, jumpHeight,0), ForceMode.Force); 
	}
}

use a small r on rigidbody2D.AddForce