Trains Problems Questions Answers

• 1. Two trains are running in opposite directions in the same speed. The length of each train is 120 meter. If they cross each other in 12 seconds, the speed of each train (in km/hr) is

  1. 30 Km/hr
  2. 36 Km/hr
  3. 80 Km/hr
  4. 90 Km/hr

  Answer :

  Option B

  Explanation:

  Distance covered = 120+120 = 240 m
  Time = 12 s
  
  Let the speed of each train = x.
  Then relative velocity = x+x = 2x
  
  2x = distance/time = 240/12 = 20 m/s
  
  Speed of each train = x = 20/2 = 10 m/s
  
  = 10*18/5 km/hr = 36 km/hr

• 2. Length of train is 130 meters and speed of train is 45 km/hour. This train can pass a bridge in 30 seconds, then find the length of the bridge.

  1. 230 meters
  2. 235 meters
  3. 240 meters
  4. 245 meters

  Answer :

  Option D

  Explanation:

  Let the length of bridge is X [as always we do :)]
  Speed of train is = 45*(5/18) m/sec = 25/2 m/sec
  Time = 30 seconds
  
  Total distance = 130+x
  We know Speed = distance/time
  so,
  \begin{aligned}
  \frac{130+x}{30} = \frac{25}{2} \\
  => 2(130+x) = 750 \\
  x = 245 \text{ meters}
  \end{aligned}
  
  So length of the bridge is 245 meters
  
  
  

• 3. A 300 meter long train crosses a platform in 39 seconds while it crosses a signal pole in 18 seconds. What is the length of the platform.

  1. 310 meter
  2. 335 meter
  3. 345 meter
  4. 350 meter

  Answer :

  Option D

  Explanation:

  Speed = Distance/time = 300/18 = 50/3 m/sec
  
  Let the length of the platform be x meters
  then
  \begin{aligned}
  Distance = Speed*Time \\
  x+300 = \frac{50}{3}*39 \\
  =>3(x+300)= 1950 \\
  => x = 350 \text{ meters}
  \end{aligned}

• 4. A jogger running at 9 kmph alongside a railway track is 240 metres ahead of the engine of a 120 metre long train running at 45 kmph in the same direction. In how much time will the train pass the jogger ?

  1. 30 seconds
  2. 32 seconds
  3. 34 seconds
  4. 36 seconds

  Answer :

  Option D

  Explanation:

  Speed of train relative to jogger = (45-9) = 36 kmph
  = 36*(5/18) = 10 m/sec
  
  Distance to cover = 240 + 120 = 360 metres
  
  Time = Distance/Speed
  So,
  \begin{align}
  Time = \frac{360}{10} = 36 \text{ Seconds}
  \end{align}

• 5. A train running at the speed of 60 km/hr crosses a pole in 9 seconds. Find the length of the train.

  1. 150 meter
  2. 145 meter
  3. 140 meter
  4. 135 meter

  Answer :

  Option A

  Explanation:

  Speed = 60*(5/18) m/sec = 50/3 m/sec
  
  Length of Train(Distance) = Speed * Time
  
  \begin{aligned}
  = \frac{50}{3}*9 = 150 meter
  \end{aligned}

• 6. A train speeds past a pole in 15 seconds and a platform 100 meter long in 25 seconds. What is length of the train ?

  1. 140 meter
  2. 145 meter
  3. 150 meter
  4. 155 meter

  Answer :

  Option C

  Explanation:

  Let the length of the train is x meter and Speed of the train is y meter/second
  Then x/y = 15 [because distance/speed = time]
  => y = 15/x
  
  \begin{aligned}
  => \frac{x+100}{25} = \frac{x}{15} \\
  x = 150 \text{ meters}
  \end{aligned}
  
  So length of the train is 150 meters

• 7. How many seconds will a 500 meter long train take to cross a man walking with a speed of 3 km/hr in the direction of the moving train if the speed of the train is 63 km/hr

  1. 25 Seconds
  2. 28 Seconds
  3. 30 Seconds
  4. 35 Seconds

  Answer :

  Option C

  Explanation:

  Relative Speed = 63-3 = 60 Km/hr
  = 60 *(5/18) = 50/3 m/sec
  
  Time taken to pass the man will ne
  \begin{aligned}
  500*\frac{3}{50} = 30 \text{ seconds}
  \end{aligned}