Two blocks \( (P \text{ and } Q) \) with respectively masses \( 2 \,\text{kg} \) and \( 1.5 \,\text{kg} \) are joined by a massless thread. These blocks are mounted on a frictionless pully which is fixed on the edge of a cube \( (S) \), as shown in the figure below. Below \( P \) is positioned on the top surface which has no friction and block \( Q \) is in contact with side-surface, having coefficient friction \( \mu \). The cube \( (S) \) moves towards the right with acceleration of \( \frac{g}{2} \), where \( g \) is gravitational acceleration. During this movement the block \( P \) and \( Q \) remain stationary. The value of \( \mu \) is ______. (take \( g=10\,\text{m/s}^2 \))/page_36/extracted_5.png)
