Two trains of length 150 m and 300 m long are going parallel in opposite direction at a speed of 90 m/min and 60 m/min respectively. What is the time taken for the trains to cross each other completely?
3 minutes
The correct answer is 3 minutes.
The distance between them decreases rapidly at this combined speed. In train problems, the total distance to be covered during a complete crossing is always the sum of the lengths of the objects involved (train + train, train + platform, etc.). This is because the crossing is considered complete only when the entire length of one object has passed the entire length of the other object.
Similar Questions
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Important Questions from Relative Speed
- Ankur jogs on a circular track X at $1 \frac{2}{3}$ m/s and Mahima jogs on track Y at $2 \frac{1}{12}$ m/s. The total length of Tracks X and Y is 0.325 km. Ankur makes 9 rounds of track X in the same time Mahima makes 5 rounds of track Y. The time taken (in seconds) by Mahima to complete one round of track X is:
- Two places, A and B are 3710 kms from each other. A train leaves from A to B at the same time another train leaves B to A. The two trains meet at the end of 35 hours. If the train travelling from A to B travels 35 kmph faster than the other. Find the speed of the faster train. (In kmph)
- A truck, 1575 metres long is running at a speed of 109 km/hr. How many seconds will it take to cross a 1475 metres long train running in the same direction at a speed of 79 km/hr?
- A truck, 1600 metres long is running at a speed of 112 km/hr. How many seconds will it take to cross a 1500 metres long train running in the same direction at a speed of 82 km/hr?
- Two friends 10 km apart start running towards each other at speeds of 10 km/hr and 14 km/hr respectively. After how much time will they meet each other?
