A ball of mass 0.5 kg is attached to a string of length 50 cm. The ball is rotated on a horizontal circular path about its vertical axis. The maximum tension that the string can bear is 400 N. The maximum possible value of angular velocity of the ball in rad $\mathrm { s } ^ { - 1 }$ is,:\\
(1) 1600\\
(2) 40\\
(3) 1000\\
(4) 20