Three forces \( F_1 = 10 \,\text{N} \), \( F_2 = 8 \,\text{N} \), \( F_3 = 6 \,\text{N} \) are acting on a particle of mass \( 5 \,\text{kg} \). The forces \( F_2 \) and \( F_3 \) are applied perpendicularly so that particle remains at rest. If the force \( F_1 \) is removed, then the acceleration of the particle is: