Activating a component

Hello. I want to make it so that when this object (a projectile) collides with an enemy, it activates the particle renderer component(it is a component of the projectile), how would I do that? Here is my script so far. Thanks.

if (other.gameObject.CompareTag ("Enemy")) {
particleEmitter.Enabled = true;
Destroy (gameObject);
Destroy (other.gameObject)

Assuming that either your enemy or your projectile has a CharacterController or RigidBody, then you can use OnCollisionEnter. Because your particle renderer is a component of your projectile, when you destroy your projectile, it gets destroyed as well. You will either need to instantiate a new particleEmitter or not destroy your projectile.

//a prefab empty GameObject with the attached particleEmitter (set to emit)
var particlePrefab : GameObject

function OnCollisionEnter(collisionInfo : Collision) {
    if(collisionInfo.gameObject.tag == "Enemy") {
        Instantiate(particlePrefab, transform.position, transform.rotation);