A ball of mass 1 kg is at rest in position P by means of two light strings OP and RP. The string RP is now cut and the ball swing to position Q. If $\theta=45 ^{\circ}$ . Find the tension in the string OQ when RP is cut $(g=10 m/s^2)$

Question

$$(a)\;10 \sqrt 2 N\quad (b)\; 5 \sqrt 2 N \quad (c)\;2 \sqrt 2 N \quad(d)\;5 N$$