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