title: Unity An object reference is required to access non-static member C#
body: <p>Im trying to learn C# with Unity engine</p>
  
  <p>But a basic script like this:</p>
  
  <pre><code>using UnityEngine;
  using System.Collections;
  
  public class scriptBall : MonoBehaviour {
  
      // Use this for initialization
      void Start () {
          Rigidbody.AddForce(0,1000f,0);
      }
  
      // Update is called once per frame
      void Update () {
  
      }
  }
  </code></pre>
  
  <p>gives this error:
  Assets/Scripts/scriptBall.cs(8,27): error CS0120: An object reference is required to access non-static member `UnityEngine.Rigidbody.AddForce(UnityEngine.Vector3, UnityEngine.ForceMode)'</p>
  
  <p>i cant find a solution for my problem</p>