Q. Two trains are running in opposite directions with the same speed. If the length of each train is 120 metres and they cross each other in 12 seconds, then the speed of each train (in km/hr) is:

Option
A. 10
B. 18
C. 36
D. 72

• sorry aruna,your answer is in m/sec.
  Let the speed of the train is x
  Realtive speed between the trains =2x
  time =12
  distance=240
  2x=240/12
  2x=20
  x=10 m/sec
  x=10*18/5= 36km/h.
  
• 11 years agoHelpfull: Yes(11) No(1)
• Option A 10 kM/hR
  Let the speed of the train is x
  Realtive speed between the trains =2x
  time =12
  distance=240
  2x=240/12
  2x=20
  x=10 km/hr
  
• 12 years agoHelpfull: Yes(1) No(6)
• total distance/total speed=time to cross
  240/(speed of t1+speed of t2)=12
  240/12=speed of t1+t2=20m/s
  so,each 10*18/5=36km/hr
  
• 9 years agoHelpfull: Yes(1) No(0)
• ans:72
  x=120+120/12
  x=20*18/5
  x=72km/hr
• 8 years agoHelpfull: Yes(1) No(1)
• since length of both train is 120 so total length of train is 240 m and time is 6 sec
  speed=d/t
  =240/12=20 m/s
  so covert in km/hr hence , 18/5*20=72km/hr
  option D is correct
  
  
• 7 years agoHelpfull: Yes(1) No(0)
• 20 meter per second
  1.2km per minute
  72km per hour
  option D
• 7 years agoHelpfull: Yes(0) No(0)