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Class 10 Class 12
Two trains are heading towards each other on the same straight track with speed 15 m/sec and 10 m/sec. When they are 250 m apart the drivers of both the trains apply their brakes. If one train retards at the rate 0·5 m/s2 then what should be the retardation of the second train so that collision of two trains just averts?

Given, two trains are heading towards each other on the same straight track.

Initial relative speed of two trains,

Let 'a' be the retardation of second train.

Therefore the relative retardation is,

The collision will just avert if the relative speed of the two trains just becomes zero after travelling the distance of 250m.

Now,

∴

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