a carriaage driving through a fog passed by a man who was walking at the rate of 6 kmph in the same direction. he could see the carriage for 5 minutes and it was visible to him upto a distance of 100 m. what was the speed of the carriage in m/sec?
a)3 b)4 c)1 d)2

• speed of the person is... 6km/h = 100m/min
  so .. if carriage has a speed of x m/min .
  then relative speed of carriage = (x-100) m/min
  so time = distance/speed
  so.. 5 = 100 /( x-100)
  by solving. x=120 m/min
  so x=120/60 = 2 m/sec
  so the choice d)2 is correct....
• 12 years agoHelpfull: Yes(50) No(1)
• 6kmph===>(6*(5/18))m/s=====>5/3
  (v-(5/3)=(100/(5*60))
  =>v-(5/6)=1/3
  =>v=(5/6)+(1/6)
  v=2
• 12 years agoHelpfull: Yes(3) No(1)
• Let x be the speed of the carriage.
  Relative speed=100/(5*60)=1/3 m/sec
  speed of man in m/sec=6*5/18=5/3 m/sec
  so,
  x-5/3=1/3
  =>x=6/3
  =>2 m/sec
  final answer is d)2
• 11 years agoHelpfull: Yes(3) No(0)
• thanku abhilash... :)
• 12 years agoHelpfull: Yes(2) No(10)
• thank u abhilash for ur great solution
• 12 years agoHelpfull: Yes(1) No(3)
• speed of person=6kmph=(6*5/18)m/s=5/3 m/s=100 m/mim
  let speed of carrriage =x m/min
  since both are walking in same direction
  hence relative speed =(x-100)m/min
  time=5 min
  time=distance/speed
  5=100/x-100
  5x-500=100
  5x=600
  x=120 m/min
  2m/sec ans is d)2 .......
• 12 years agoHelpfull: Yes(0) No(0)