A train is moving at a constant speed $V$. When its driver observes another train in front of him on the same track and moving in the same direction with constant speed $u$. If the distance between the trains be $x$, then what should be the minimum retardation of the train so as to avoid collision?
A train is moving at a constant speed $V$. When its driver observes another train in front of him on the same track and moving in the same direction with constant speed $u$. If the distance between the trains be $x$, then what should be the minimum retardation of the train so as to avoid collision?
- A
$(V + u)^2\,/x$
- B
$(V -u)^2\,/x$
- C
$(V + u)^2\,/2x$
- D
$(V -u)^2\,/2x$
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- [JEE MAIN 2022]