Question
Train A running with a sped of 162 km/h crosses a
vertical pole in 10 seconds. Speed of train A is 7 m/s less than speed of train B, and length of train B is 80 metres less than length of train A. Find the time taken by train B to cross a 280 metre long tunnel.Solution
Speed of train A = 162 × 5/18 = 45 m/s Speed of train B = 52 m/s Length of train A = 10 × 45 = 450 metres Length of train B = 450 – 80 = 370 metres Desired time = (370 + 280)/52 = 12.5 seconds
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