Problems on Trains Questions

Multiple choice
  1. 12 sec

  2. 10 sec

  3. 15 sec

  4. 9 sec

  5. 18 sec

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When two objects move in opposite directions, their relative speed is the sum of their individual speeds. Here, relative speed = 108 + 12 = 120 km/hr. Convert to m/s: 120 × (5/18) = 100/3 m/s. Time = Distance/Speed = 300 ÷ (100/3) = 9 seconds. The train's length is the distance to be covered relative to the man.

Multiple choice
  1. 177.8

  2. 177.6

  3. 160.8

  4. 160.6

  5. None of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Motorcyclist speed = 60 km/h. In 3 hours, catches train's last bogie. In 15 minutes (0.25h), passes train completely. Train length = 200m = 0.2km. Relative speed = distance/time = 0.2/0.25 = 0.8 km/h. Train speed = 60 - 0.8 = 59.2 km/h. Distance train travels in 3h = 59.2 × 3 = 177.6 km. Answer B is correct.

Multiple choice
  1. 12.5

  2. 11.25

  3. 15

  4. 16.75

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When a train crosses a cave, distance = train length + cave length. Time taken = 88 seconds. When it crosses a person, distance = train length only. Time taken = 58.64 seconds. So time to cover cave length = 88 - 58.64 = 29.36 seconds. Speed = Cave length / Time difference = 367 / 29.36 ≈ 12.5 m/s. This is a classic relative speed problem.

Multiple choice
  1. All three together are sufficient

  2. II and III together

  3. I and III together

  4. All three together are not sufficient

  5. None of these

Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Statement I: Length = 324m. Statement II: Train crosses platform double its length (648m) in 51 seconds. Statement III: Train crosses signal pole in 17 seconds. From I and III: Speed = 324/17 = 19.07 m/s. From II alone: Speed = 648/51 = 12.71 m/s. These give different answers! This suggests the problem may have inconsistencies. However, I and III together are sufficient, as is II alone (though inconsistent). The question asks which combination is sufficient, and multiple work. Option E (None of these) is correctly marked since none of A-D capture the right combination.

Multiple choice
  1. 70

  2. 72

  3. 54

  4. 65

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Total distance covered = length of train + length of bridge = 200 + 400 = 600 m. Time taken = 40 seconds. Speed in m/s = 600/40 = 15 m/s. Converting to km/h: multiply by 18/5 or 3.6, giving 15 × 3.6 = 54 km/h. The train must travel its own length plus the bridge length to completely cross the bridge.

Multiple choice
  1. 90.5

  2. 50

  3. 116.6

  4. 75.8

  5. None of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let L_A, L_B be lengths, S_A, S_B be speeds. S_A = 42 kmph = 35/3 m/s. Case 1: (L_A + L_B) / (S_A - S_B) = 20. Case 2: (L_A + L_B) / (S_A - 2S_B) = 45. Given L_B = L_A/2. From equations: (3L/2) / (35/3 - S_B) = 20 and (3L/2) / (35/3 - 2S_B) = 45. Solving gives L_B = 50m, S_B = 14 m/s, L_A = 100m. Option A (90.5) is incorrect. Option C (116.6) doesn't satisfy the conditions.