A goods train runs at the speed of 72 kmph and crosses a 250 m long platform…
2024
A goods train runs at the speed of 72 kmph and crosses a 250 m long platform in 26 seconds. What is the length of the goods train?
- A.
230 m
- B.
240 m
- C.
260 m
- D.
270 m
Attempted by 11 students.
Show answer & explanation
Correct answer: D
Concept: When a train crosses a stationary object such as a platform, the total distance it travels equals the sum of the train's own length and the platform's length. This distance is covered at the train's speed over the given crossing time, so Distance = Speed × Time.
Application:
Convert the train's speed from km/h to m/s: 72 × 5/18 = 20 m/s.
Total distance covered while crossing the platform in 26 seconds = Speed × Time = 20 × 26 = 520 m.
Since total distance = train length + platform length, train length = 520 − 250 = 270 m.
Cross-check: Substituting back, (270 + 250) / 26 = 520 / 26 = 20 m/s = 72 km/h, which matches the given speed — confirming the train length is 270 m.