A solid sphere of mass \( 1 \, \text{kg} \) and radius \( 1 \, \text{m} \) rolls without slipping on a fixed inclined plane with an angle of inclination \( \theta = 30^\circ \) from the horizontal. Two forces of magnitude \( 1 \, \text{N} \) each parallel to the incline, act on the sphere, both at distance \( r = 0.5 \, \text{m} \) from the centre of the sphere, as shown in the figure. The acceleration of the sphere down the plane is ______ \( \text{m s}^{-2} \). (Take \( g = 10 \, \text{m s}^{-2} \).)
