Question

here is your question in the attachment ​

Answer 1

All the four persons will meet at the centre O of the square. Each person covers a displacement

S =

$\frac{1}{2} \times \sqrt{d^{2} + d^{2} } \\ = \frac{d}{ \sqrt{2} }$

Component of velocity 'v' towards O ,

v = v cos 45°

$= \frac{v}{ \sqrt{2} }$

Hence required time,

$t = \frac{s}{v} = \frac{ \frac{d}{ \sqrt{2} } }{ \frac{v}{ \sqrt{2} } } = \frac{d}{v}$

Answer 2

Step-by-step explanation:

all four person will meet at centre O of a square. each person cover displacement,

s=1/2.√d^2+d^2

=d/√2

component of velocity v towards O

v'= v cos 45°

=v/√2

.•. required time

t=s/v'

=d/√2/v/√2

=d/v