//acceleration of the rigidbody not calculated in Unity - calculate using components of forces along slope
    private void UpdateAcceleration()
    {
        float resultant = forcesScript.GetParallelForce() - forcesScript.GetFriction();     //resultant along slope

        if (resultant < 0 || rb.velocity.z == 0)
        {
            accelerationText.text = "0";
        }
        else
        {
            float acceleration = resultant / mass;
            accelerationText.text = acceleration.ToString("F1");
        }
    }
 //acceleration of the rigidbody not calculated in Unity - calculate using components of forces along slope
 private void UpdateAcceleration()
 {
     resultant = forcesScript.GetParallelForce() - forcesScript.GetFriction();     //resultant along slope
     if (resultant < 0)
     {
         accelerationText.text = "0";
         //set the velocity to 0 because it shouldn't be moving
         rb.velocity = new Vector3(rb.velocity.x, rb.velocity.y, 0);     //Unity 2017 does not have accurate friction calculation, so mass slides before it should
     }
     else
     {
         float acceleration = resultant / mass;
         accelerationText.text = acceleration.ToString("F2");
     }
 }