A train 125m long is running at 50 km/ hr. In what time will it pass a man ,…
2024
A train 125m long is running at 50 km/ hr. In what time will it pass a man , running at 5 km/hr in the same direction in which the train is going?
- A.
22 sec
- B.
10 sec
- C.
11 sec
- D.
19 sec
Attempted by 1 students.
Show answer & explanation
Correct answer: B
The correct answer is Option B: 10 sec.
Step-by-Step Solution
Understand Relative Speed: When two objects move in the same direction, their relative speed is the difference between their individual speeds.
Train speed = 50 km/hr
Man speed = 5 km/hr
Relative speed = 50 - 5 = 45 km/hr.
Convert Speed to Meters per Second (m/s): To match the distance in meters, convert the speed from km/hr to m/s by multiplying by 5/18.
Relative speed in m/s = 45 * (5/18)
45 * 5 = 225
225 / 18 = 25/2 m/s (or 12.5 m/s).
Calculate Time: Time is calculated by dividing the distance (length of the train) by the relative speed.
Distance = 125 m
Time = 125 / (25/2)
Time = 125 * (2/25)
Time = 5 * 2 = 10 seconds.