A ball of mass \( 0.5 \, \text{kg} \) is attached to a string of length \( 50 \, \text{cm} \). The ball is rotated on a horizontal circular path about its vertical axis. The maximum tension that the string can bear is \( 400 \, \text{N} \). The maximum possible value of angular velocity of the ball in \( \text{rad}/\text{s} \) is:
