Bridge length from mixed time – fast train A 150 m train at 90 km/h crosses a bridge in 26 s. What is the bridge length?
Aptitude
Problems on Trains
Difficulty: Easy
Choose an option
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A500 m
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B600 m
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C659 m
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D550 m
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ENone of these
Answer
Correct Answer: 500 m
Explanation
Introduction / Context:Calculate total distance covered during the crossing time, then subtract train length to get the bridge length. Unit conversion remains essential.
Given Data / Assumptions:
- L = 150 m.
- v = 90 km/h = 25 m/s.
- t = 26 s.
Concept / Approach:D = v * t; bridge = D - L.
Step-by-Step Solution:
D = 25 * 26 = 650 mBridge = 650 - 150 = 500 mVerification / Alternative check:At 25 m/s, 26 s gives 650 m which equals 150 m train + 500 m bridge.
Why Other Options Are Wrong:600 m and 550 m overshoot; 659 m is not founded on the given numbers.
Common Pitfalls:Forgetting to subtract the train's own length from the total distance.
Final Answer:500 m