The famous Denali Star train starts from anchorge & travels towards fair banksat speed 50 mph.After some time another train Glacier Discovery Train( At parallel track) at fair banks And moves towards Anchorge at a speed of 70 mph. Both the trains Denali star & Glacier discovery have a length 1/6 miles each .After the trains meet how many seconds will faster train take to overtake the slower one

• total distance = (1/6)+(1/6) = 1/3 miles
  relative speed = (50+70) mph = 120 mph
  time taken = (1/3)/(120) hours = 10 seconds
• 9 years agoHelpfull: Yes(34) No(2)
• Total distance = 1/6 + 1/6 = 1/3
  Since trains travelling in same direction, we have to subtract speed...
  So relative speed = 70-50 = 20
  Time taken = (1/3)/20 = 1/60 hours => (1/60)*60 mins => 1 mins => 60 sec
  
  Ans : 60 sec
• 9 years agoHelpfull: Yes(22) No(39)
• distance = 2 x (1/6)= 1/3
  relative speed = 50 +70=120
  time = 1/3mile / 120 mph= 10 seconds
  
  relative speed should be added because they are going in opp. direction
• 9 years agoHelpfull: Yes(8) No(1)
• wrong...
  option is -
  a) 60 sec
  b) 20 sec
  c) 180 sec
  d) 32 sec
• 9 years agoHelpfull: Yes(1) No(1)
• @vivek gupta....check your options again answer is 10 seconds for sure..or this might be the dummy question(i dont know whether it is really there or a myth..i just heard about it)
  @saraswathy.. u can not subtract to find relative speed since they are moving in opposite directions
• 9 years agoHelpfull: Yes(1) No(0)
• 0sec ....since both trains met and faster train already overtaken the slower one.
• 9 years agoHelpfull: Yes(0) No(4)
• The trains are in opposite direction because 1st train starts from anchorge & 2nd train towards anchorage.
  The relative spped of the trains = 70+50 = 120m/h
  distance = (1/6)+(1/6) = 1/3
  time = (1/3)/120 = 10 seconds
• 9 years agoHelpfull: Yes(0) No(1)
• Wrong Question! Direction of two trains not clear from the question.
  
• 9 years agoHelpfull: Yes(0) No(4)
• as trains are moving in opposite direction,
  miles/hour to meter/sec for speed(70+50=120)=53.64
  miles to meter for total distance(1/6+1/6)=1/3=535.91
  t=d/s =535.91/53.64=9.98 i.e.=10 sec
• 9 years agoHelpfull: Yes(0) No(1)