A boy is pushing a ring of mass 2 kg and radius 0.5 m with a stick as shown in the figure. The stick applies a force of 2 N on the ring and rolls it without slipping with an acceleration of $0.3 \mathrm{~m} / \mathrm{s}^2$. The coefficient of friction between the ground and the ring is large enough that rolling always occurs and the coefficeint of friction between the stick and the ring is $(\mathrm{P} / 10)$. The value of P is