Problems on Trains Questions

Multiple choice
  1. $675$ m
  2. $505$ m
  3. $847$ m
  4. $620$ m
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Speed = 54 km/hr = 54 * (5/18) = 15 m/s. Time = 1.5 minutes = 90 seconds. Total distance = Speed * Time = 15 * 90 = 1350 m. Since train length = platform length, 2 * platform = 1350, so platform = 675 m.

Multiple choice
  1. $85$ km/hr
  2. $50$ km/hr
  3. $55$ km/hr
  4. $25$ km/hr
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Relative speed = (66 + 88) m / (0.168 * 60) s = 154 / 10.08 = 15.27 m/s. 15.27 m/s * 3.6 = 55 km/hr. Since they are in the same direction, V1 - V2 = 55. V1 - 30 = 55 => V1 = 85 km/hr.

Multiple choice
  1. $200$ km
  2. $220$ km
  3. $240$ km
  4. $280$ km
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Goods train starts at 1 pm, Express at 3 pm. By 3 pm, goods train has traveled 2 hours * 40 km/hr = 80 km. Relative speed = 60 - 40 = 20 km/hr. Time to overtake = 80 km / 20 km/hr = 4 hours. Distance from Delhi = 60 km/hr * 4 hours = 240 km.