Two trains travelling on same track are approaching each other with equal speeds of 40, m/s . driver

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2.Motion in Straight Line

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Two trains travelling on the same track are approaching each other with equal speeds of $40\, m/s$. The drivers of the trains begin to decelerate simultaneously when they are just $2.0\, km$ apart. Assuming the decelerations to be uniform and equal, the value of the deceleration to barely avoid collision should be.........$m/{s^2}$

A$11.8$

B$11.0$

C$2.1$

D$0.8$

Solution

(d) Both trains will travel a distance of $1\, km$ before to come in rest.
In this case by using ${v^2} = {u^2} + 2as$
$ \Rightarrow 0 = {(40)^2} + 2a \times 1000$
$ \Rightarrow a = – 0.8\;m/{s^2}$

Standard 11

Physics

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(AIIMS-2001)

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(JEE MAIN-2018)

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medium

(AIIMS-2019)

Solution

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