Let \( C \) be the largest circle centred at \( (2, 0) \) and inscribed in the ellipse \( \frac{x^{2}}{36} + \frac{y^{2}}{16} = 1 \). If \( (1, \alpha) \) lies on \( C \), then \( 10\alpha^{2} \) is equal to ______.