I need help in using Impulse Force (2D)

Questions & Answers
1

I am a beginner at Unity, so I am just trying to do some basic stuff. I wanted to try to
make a bar move horizontally in 2D mode, and I did it. Then I noticed it was taking time to start
moving,accelerate, and change direction because it follows force = mass x acceleration, but I don’t want that.
With the docs and scripting API, I found that I should use a 2D Impulse force to solve my problem.
I just don’t know how to fix my current code to use the impulse force instead, even though I have
tried it many times in different ways. This is the code I am using:

   using UnityEngine;
        using System.Collections;
        
        public class Control : MonoBehaviour {
        	
        	
        	public float speed;
        	
        	private Rigidbody2D rb;
        	
        	void Start ()
        	{
        		rb = GetComponent<Rigidbody2D>();
        	}
        	
        	void FixedUpdate ()
        	{
        		float moveHorizontal = Input.GetAxis ("Horizontal");
        
        		
        		Vector2 movement = new Vector2 (moveHorizontal, 0);
        		
        		rb.AddForce (movement * speed);
        	}
        }
2

Ok I lied. It seems ForceMode has indeed been added to Rigidbody2D.

http://docs.unity3d.com/ScriptReference/Rigidbody2D.AddForce.html

rb.AddForce(Vector2(x,y),ForceMode2D.Impulse);