A train travelling at 44 km/h crosses a man walking with a speed of 8 km/h, in the same direction, in 15 seconds. If the train crosses a woman coming from the opposite direction in 10 seconds, then what is the speed (in km/h) of the woman?
Show answer & explanation
Correct answer: D
Explanation
Correct answer is option 4 i.e. 10
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Concept |
Understanding |
Application |
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Relative speed (in same direction) = Speed1 – Speed2
Relative speed (in opposite direction) = Speed1 + Speed2
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Speed of train = 44 km/h Speed of man = 8 km/h
Train crosses man walking insame direction in 10 seconds |
Relative speed of train with respect to man =44-8= 36 km/hr= 36x5/18 = 10m/s
Hence, Distance travelled in 15 seconds (Length of train) = 15 x10 = 150 meter |
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Let speed of woman = X km/hr
Train crosses a woman coming from the opposite direction in 10 seconds |
Relative speed of train with respect to woman =44+ X
150 = (44+ X) x5/18x 10 ⇒ X = 10 |