A uniform rod \( KJ \) of weight \( w \) shown in the figure rests against a frictionless vertical wall at the point \( K \) and a rough horizontal surface at point \( J \). It is given that \( w = 10 \, \text{kN} \), \( a = 4 \, \text{m} \), and \( b = 3 \, \text{m} \).
The minimum coefficient of static friction that is required at the point \( J \) to hold the rod in equilibrium is _________ (round off to three decimal places).
