constructor() {

    this.acceleration = createVector(0, 0);

    this.position = createVector(width / 10, height / 2);

    this.velocity = createVector(0, 0);

    this.mass=1;

  }

​

  applyForce(force) {

    force.div(this.mass);

    this.acceleration.add(force); //assuming mass=1

  }

​

  update() {

    this.position.add(this.velocity);

    this.velocity.add(this.acceleration);

    this.acceleration.set(0, 0); //needs to be at the end of the "update"

  }

​

  display() {

    stroke(116, 238, 21);

    strokeWeight(4);

    fill(0, 102, 203);

    ellipse(this.position.x, this.position.y, 50, 50);

  }

​

  edges() {

    // checking the edges to make sure the ball doesn't go off screen

    if (this.position.y >= height) {

      this.position.y = height;

      this.velocity.y *= -1;

    }

    if (this.position.x >= width) {

      this.position.x = width;

      this.velocity.x *= -1;

      }

    if (this.position.x <= 0){

      this.position.x=0;

      this.velocity.x *= -1;

    }

    if (this.position.y <= 0){

      this.position.y=0;

      this.velocity.y *= -1;

    }

  }

}

​