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- General Aptitude
- Problems on Trains
- Important Formulas
Non-moving objects | ||||||||||||||||
(i) The time taken by the train to cross a stationary object (e.g.) is (lamp post, pole, standing man) which is of negligible length is given by | ||||||||||||||||
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Note: | ||||||||||||||||
If the object is of some length (e.g, bridge, a tunnel, platform, another train) then, | ||||||||||||||||
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Moving objects | ||||||||||||||||
(ii) If the object is moving and is of negligible length (e.g : a train crosses a running man) is given by | ||||||||||||||||
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(iii) If the object is moving and has some length then, | ||||||||||||||||
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Note: | ||||||||||||||||
If the object is moving and direction put –ve sign before v. | ||||||||||||||||
(iv) Two trains crossing each other in both directions | ||||||||||||||||
Length of 1st train = L1 | ||||||||||||||||
Length of 2nd train = L2 | ||||||||||||||||
They are crossing each other in opposite directions, in t1 seconds. | ||||||||||||||||
They are crossing each other in same direction in t2 seconds then, | ||||||||||||||||
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(v) If two trains start at the same time from points A and B towards each other and after crossing they take a and b seconds in reaching B and A respectively, then | ||||||||||||||||
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