Making force 0 at some point.

I am adding force(for projectile motion) once i release my mouse button.

rigidbody.AddRelativeForce(10, 10, 10);

Once it reaches the trigger point i want this force to be 0 .i.e the ball should fall down with the gravity.
So how to make this force 0?

PS : The trigger point is somewhere far.

is the trigger an actual object?

basically you need to add a bool AND together the if statement with the bool and change the bool based on the trigger.

public bool TriggerHit = false;

if(input.getmousebuttonup(0) && TriggerHit == false)
//you can add something to do here if the trigger is hit
 or you can just do nothing and simply stop adding force

//script atttached to gameobject with trigger collider

void OnTriggerEnter(collider ColliderOfObject)
if (ColliderofObject.gameobject.tag == "name of your ball")

ColliderofObject.gameobject.getComponent<Script That adds force>().TriggerHit = true;