Question
Two trains of length 420 metres and 320 metres are
moving in opposite directions with speeds 15 m/s and 20 m/s. If initially they are 100 metres apart, then find the time taken by them to cross each other.Solution
Relative speed = 15 + 20 = 35 m/s (When two objects are moving in opposite direction, so speeds are added)
Therefore, required time = (420 + 320 + 100) ÷ 35 = (840 ÷ 35) = 24 seconds
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