Question
Train A, moving at a speed of 90 km/h, passes a
stationary pole in 9.4 seconds. When encountering Train B, which is traveling towards it at a speed of 54 km/h, Train A takes 12.5 seconds to completely pass Train B. Calculate the length of Train B.Solution
Speed of train A = 90 × 5/18 = 25 m/s Length of train A = 25 × 9.4 = 235 metres Let length of train B = ‘l’ metres Speed of train B = 54 × 5/18 = 15 m/s Relative speed if train A with respect to train B = 15 + 25 = 40 m/s So, I + 235 = 40 × 12.5 = 500 So, l = 265 metres
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