How to jump in 2D?

OK, this may be a noob question, but I have this script for my 2D platformer, and I am not sure what is wrong with it. Here is my code (C#):

 using UnityEngine;
 using System.Collections;
 
 public class PlayerMovement : MonoBehaviour {
 
     public Transform groundCheck;
 
     public float jumpForce; 
     public bool jump = false;
     private bool grounded = false;
 
 
     void Start () {
     
     }
     
 
     void Update () 
     {
         float x = Input.GetAxis ("Horizontal");
         transform.Translate (x / 10, 0f, 0f);
 
         grounded = Physics2D.Linecast(transform.position, groundCheck.position, 1 << LayerMask.NameToLayer("Ground"));
 
         if (Input.GetButtonDown ("Jump") && grounded) 
         {
             jump = true;
         }
 
 
     }
 
     void FixedUpdate ()
     {
         if (jump) {
             rigidbody2D.AddForce(new Vector2(0f, jumpForce));
             jump = false;
                 }
     }
 
 
     void OnCollisionEnter2D ()
     {
         if (gameObject.tag == "Floor") {
                         grounded = true;
                 } else {
             grounded = false;
                 }
     }
 }

I also have a sprite called 'Floor' and that has the layer 'Ground'.

When I press SPACE, the sprite does not move at all.

All help is appreciated! I hope I get an answer!