Apply impulse to a Node

Cocos Creator
1

Hi guys,
I’m new to Cocos and I’m trying to apply an impulse to my node when I’m pressing KeyCode.SPACE.
In particular I’ve a Node with RigidBody2D component and a script.
Inside the script I’m trying to do this, but doesn’t works:

onKeyDown(keyboardEvent: EventKeyboard): void {
    switch (keyboardEvent.keyCode) {
      case KeyCode.SPACE:
        this.rigidBody.applyLinearImpulseToCenter(this.force, false);
        break;
    }
  }

The force is a Vec2:

force = new Vec2(0, -25);

Any suggestions?
Thank you!!

2

I solved!
In Cocos Y coordinates works differently other engines/frameworks!
Positives coords go up, negatives coords go down.