Adds a torque to the rigidbody relative to the rigidbodie's own coordinate system.

As a result the rigidbody will start spinning around the torque axis.

	// Spins the rigidbody around its own y-axis
	function FixedUpdate () {
		rigidbody.AddRelativeTorque (Vector3.up * 10);
	}

using UnityEngine;
using System.Collections;

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

import UnityEngine
import System.Collections

public class Example(MonoBehaviour):

	def FixedUpdate() as void:
		rigidbody.AddRelativeTorque((Vector3.up * 10))

Adds a torque to the rigidbody relative to the rigidbodie's own coordinate system.

As a result the rigidbody will start spinning around the torque axis.

	// Spins the rigidbody around its own y-axis
	function FixedUpdate () {
		rigidbody.AddRelativeTorque (0, 10, 0);
	}

using UnityEngine;
using System.Collections;

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

import UnityEngine
import System.Collections

public class Example(MonoBehaviour):

	def FixedUpdate() as void:
		rigidbody.AddRelativeTorque(0, 10, 0)

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