Acceleration/Deacceleration

[carstenht]

Im making a small "physics" app that accelerates a picture box, and then deaccelerate it until it stops. I have the acceleration working, but the deacceleration is giving me problems:

// Accelerate
private void timer1_Tick(object sender, EventArgs e)
        {
            cmdStartStop.Text = "Stop Simulation";
            box.Left += x;
            velocity += acceleration;
            x += velocity;
            lblPos.Text = "Position: " + x;
            lblVel.Text = "Velocity: " + velocity;
            lblAcc.Text = "Acceleration: " + acceleration;

        }

private void timer2_Tick(object sender, EventArgs e)
// Deaccelerate
        {
            while (velocity > 0)
            {
                box.Left += x;
                velocity -= acceleration;
                x += velocity;
                lblPos.Text = "Position: " + x;
                lblVel.Text = "Velocity: " + velocity;
                lblAcc.Text = "Acceleration: " + acceleration;

            }
        }

I start and stop the simulation with a button.
timer2 is disabled at load
button activates timer1
button then deactivate timer1 and activate timer2