Two boys are standing at the ends A and B of a ground where AB = a. The boy at B starts running in a direction perpendicular to AB with velocity v1. The boy at A starts running simultaneously with velocity v and catches the other boy in a time t, where t is
The correct option is C.
Let two boys meet at point C after time 't' from the starting.Then AC=vt, BC=v1t
Therefore in a right angle triangle ABC,
(AC)2=(AB)2+(BC)2⇒v2t2=a2+v21t2
v2t2−v21t2=a2
t2(v2−v21)=a2
⇒ t=√a2v2−v21.