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Four children are standing at the corner...

Four children are standing at the corners A, B, C and D of a square of side l. They simultaneously start running such that A runs towards B, B towaards C, C runs towards D and D runs towards A, each with a velocity v.They will meet after a time

A

`sqrt(2)l//v`

B

`l//v`

C

`l//sqrt(2)v`

D

`4l//v`

Text Solution

Verified by Experts

The correct Answer is:
b
Displacement = AO = d/2 `cos 45 = d//sqrt(2)`
velocity ` = v cos 45` along `AO = v//sqrt(2)`
time ` = (d//sqrt(2))//(v//sqrt(2)) = d//v`
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