Question

two men P and Q are standing at corners A and B of square ABCD of side 8m. they start moving along the track with constant speed 2m/s and 10m/s respectively. find the time when they will meet for the first time.

Answer 1

Lets see if person at point A is stationary then speed of person at point B will be 8m/s.

Speed = 8m/s

Distance = 8*3 = 24 m

Time = D/S = 24/8 = 3sec.

Answer 2

question can be solved using relative velocity / speed concept . consider the body A to be at rest , so body B will have speed 10 - 2 = 8m/s .

now to meet point A body B has to move three sides of square , i.e. 8*3 = 24 m

dist.= 24m

speed=8m/s

therefore time taken = dist./speed=24/8= 3 sec.

hope it helped .