Question
Two trains of length 300 metres and 280 metres are
moving in opposite directions with speeds 12 m/s and 18 m/s. If initially they are 200 metres apart, then find the time taken by them to cross each other.Solution
Relative speed = 12 + 18 = 30 m/s (When two objects are moving in opposite direction, so speeds are added)
Therefore, required time = (300 + 280 + 200) ÷ 30 = (780 ÷ 30) = 26 seconds
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