question_answer

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\[{{v}_{1}}\]? The boy at A starts running simultaneously with velocity\[v\]and catches the other boy in a time t, where t is

A)  \[\frac{a}{\sqrt{{{v}^{2}}+v_{1}^{2}}}\]

B)         \[\sqrt{\frac{{{a}^{2}}}{{{v}^{2}}-v_{1}^{2}}}\]

C)  \[\frac{a}{(v-{{v}_{1}})}\]           

D)         \[\frac{a}{(v+{{v}_{1}})}\]