Rigidbody.AddForce

function AddForce (force : Vector3, mode : ForceMode = ForceMode.Force) : void

Description

Adds a force to the rigidbody. As a result the rigidbody will start moving.

JavaScript

// Adds a force upwards in the global coordinate system

function FixedUpdate () {
    rigidbody.AddForce (Vector3.up * 10);
}

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    void FixedUpdate() {
        rigidbody.AddForce(Vector3.up * 10);
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    def FixedUpdate():
        rigidbody.AddForce((Vector3.up * 10))

function AddForce (x : float, y : float, z : float, mode : ForceMode = ForceMode.Force) : void

Description

Adds a force to the rigidbody. As a result the rigidbody will start moving.

JavaScript

// Adds a force upwards in the global coordinate system

function FixedUpdate () {
    rigidbody.AddForce (0, 10, 0);
}

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    void FixedUpdate() {
        rigidbody.AddForce(0, 10, 0);
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    def FixedUpdate():
        rigidbody.AddForce(0, 10, 0)

If you want to apply a force over several frames you should apply it inside FixedUpdate instead of Update.