A 250 m long train overtakes a man moving at a speed of 7 km/h (in same direction) in 36 seconds. How much time (in seconds) will it take this train to completely cross another 415 m long train, moving in the opposite direction at a speed of 82 km/h?

This question was previously asked in
RPF Constable 2024 Official Paper (Held On: 02 Mar, 2025 Shift 1)
View all RPF Constable Papers >
  1. 17
  2. 31
  3. 30
  4. 21

Answer (Detailed Solution Below)

Option 4 : 21
Free
RPF Constable Full Test 1
3.9 Lakh Users
120 Questions 120 Marks 90 Mins

Detailed Solution

Download Solution PDF

Given:

A 250 m long train overtakes a man moving at a speed of 7 km/h (in same direction) in 36 seconds.

Another 415 m long train is moving in the opposite direction at a speed of 82 km/h.

Formula used:

Relative Speed (same direction) = Speed of Train - Speed of Man

Speed = Distance / Time

Relative Speed (opposite direction) = Speed of Train + Speed of Another Train

Time to cross = Total Distance / Relative Speed

Calculation:

First, find the speed of the train:

Let the speed of the train be x km/h.

Relative Speed (same direction) = x - 7 km/h.

Distance = 250 m = 0.25 km.

Time = 36 seconds = 36/3600 hours = 0.01 hours.

Speed = Distance / Time

⇒ x - 7 = 0.25 / 0.01

⇒ x - 7 = 25

⇒ x = 32 km/h

Next, find the time to cross the other train:

Relative Speed (opposite direction) = 32 + 82 = 114 km/h.

Total Distance = 250 m + 415 m = 665 m = 0.665 km.

Time to cross = Total Distance / Relative Speed

⇒ Time = 0.665 / 114

⇒ Time = 0.00583 hours

⇒ Time = 0.00583 × 3600 seconds

⇒ Time ≈ 21 seconds

∴ The correct answer is option (4).

Latest RPF Constable Updates

Last updated on Jun 2, 2025

-> The Railway Recruitment Board has released the RPF Constable 2025 Response Sheet on 24th March 2025. As per the official notice, the RPF Constable Answer Key will be available from 24th March 2025 to 29th March 2025. 

-> The RRB ALP 2025 Notification has been released on the official website. 

-> The Examination was held from 2nd March to 18th March 2025. Check the RPF Exam Analysis Live Updates Here.

-> RPF Constable 2025 application status was released in January 20, 2025.

More Problem on Trains Questions

More Speed Time and Distance Questions

Get Free Access Now
Hot Links: teen patti live teen patti list teen patti joy mod apk teen patti download apk teen patti gold download apk